Summary:
We now use __stack_pointer global and global.get/global.set instruction.
This fixes the checking routine for stack_pointer writes accordingly.
This also fixes the existing __stack_pointer test in reg-stackify.ll:
That test used to pass not because of __stack_pointer clashes but
because the function `stackpointer_callee` was not marked as `readnone`,
so it was assumed to possibly write to memory arbitraily, and
`global.set` instruction was marked as `mayStore` in the .td definition,
so they were identified as intervening writes. After we added `readnone`
to its attribute, this test fails without this patch.
Reviewers: dschuff, sunfish
Subscribers: jgravelle-google, sbc100, llvm-commits
Differential Revision: https://reviews.llvm.org/D56094
llvm-svn: 350906
Summary:
This is a third attempt, but this time we have vetted it on Windows
first. The previous errors were due to an uninitialized class member.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D56560
llvm-svn: 350901
This is a second attempt at r350778, which was reverted in
r350789. The only change is that the unimplemented-simd128 feature has
been renamed simd128-unimplemented, since naming it
unimplemented-simd128 somehow made the simd128 feature flag enable the
unimplemented-simd128 feature on Windows.
llvm-svn: 350791
Summary:
This replaces the old ad-hoc -wasm-enable-unimplemented-simd
flag. Also makes the new unimplemented-simd128 feature imply the
simd128 feature.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits, alexcrichton
Differential Revision: https://reviews.llvm.org/D56501
llvm-svn: 350778
Summary:
Looks like many passes print its pass description as a debug message at
the start of each pass, so added that to (mostly newly added) other
passes as well.
Reviewers: dschuff
Subscribers: jgravelle-google, sbc100, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56142
llvm-svn: 350771
Summary:
For some reason the backend assumed that the condition mask would be
the first argument to the LLVM intrinsic, but everywhere else the
condition mask is the third argument.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56412
llvm-svn: 350746
Summary:
StoreResults pass does not optimize store instructions anymore because
store instructions don't return results values anymore. Now this pass is
used solely for memory intrinsics, so update the pass name accordingly
and fix outdated pass descriptions as well.
This patch does not change any meaningful behavior, but not marked as
NFC because it changes a comment check line in a test case.
Reviewers: dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfiish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56093
llvm-svn: 350669
Summary:
FixIrreducibleControlFlow and LateEHPrepare both possibly modify CFG and
create new registers. There seems to be no reason these passes go after
register-related optimization passes (PrepareForLiveIntervals,
OptimizeLiveIntervals, StoreResults, RegStackify, and RegColoring), and
this also possibly create new optimization opportunities. I think we
should put all current and future optimization passes before RegStackify
(and related passes) unless there's a reason not to.
Reviewers: kripken
Subscribers: dschuff, sbc100, sunfish, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D56356
llvm-svn: 350596
Summary:
We don't need to explicitly use `NI` anymore because we now don't use
`let` statements within the definitions.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56376
llvm-svn: 350594
Move the check for -1 and identical values outside the vector sorting code.
Compare functions need to be able to compare identical elements to be
conforming.
llvm-svn: 350379
Summary:
Irreducible control flow is not that rare, e.g. it happens in malloc and
3 other places in the libc portions linked in to a hello world program.
This patch improves how we handle that code: it emits a br_table to
dispatch to only the minimal necessary number of blocks. This reduces
the size of malloc by 33%, and makes it comparable in size to asm2wasm's
malloc output.
Added some tests, and verified this passes the emscripten-wasm tests run
on the waterfall (binaryen2, wasmobj2, other).
Reviewers: aheejin, sunfish
Subscribers: mgrang, jgravelle-google, sbc100, dschuff, llvm-commits
Differential Revision: https://reviews.llvm.org/D55467
Patch by Alon Zakai (kripken)
llvm-svn: 350367
Summary:
The previously introduced new operand type for br_table didn't have
a disassembler implementation, causing an assert.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56227
llvm-svn: 350366
Summary:
Instead of asserting on certain kinds of malformed instructions, it
now still print, but instead adds an annotation indicating the
problem, and/or indicates invalid_type etc.
We're using the InstPrinter from many contexts that can't always
guarantee values are within range (e.g. the disassembler), where having
output is more valueable than asserting.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56223
llvm-svn: 350365
Summary:
This was previously ignored and an incorrect value generated.
Also fixed Disassembler's handling of block_type.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56092
llvm-svn: 350270
Summary:
These instructions are currently unused in our backend, but for
completeness it is good to support them, so they can be used with
the assembler in hand-written code.
Tests are very basic, signature support missing much like other blocks.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55973
llvm-svn: 350079
Summary:
It does so using a simple nesting stack, and gives clear errors upon
violation. This is unique to wasm, since most CPUs do not have
any nested constructs.
Had to add an end of file check to the general assembler for this.
Note: if/else/end instructions are not currently supported in our
tablegen defs, so these tests will be enabled in a follow-up.
They already pass the nesting check.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55797
llvm-svn: 350078
Summary:
This is a code size savings and is also important to get runnable code
while engines do not support v128.const.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55910
llvm-svn: 349724
Summary:
Gates v128.const, f32x4.sqrt, f32x4.div, i8x16.extract_lane_u, and
i16x8.extract_lane_u on the --wasm-enable-unimplemented-simd flag,
since these ops are not implemented yet in V8.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55904
llvm-svn: 349720
Summary:
We use `variable_ops` in the tablegen defs to denote the list of
branch targets in `br_table`, but unlike other uses of `variable_ops`
(e.g. call) the these branch targets need to actually be encoded in the
instruction. The existing tables for `variable_ops` cause not operands
to be accepted by the assembly matcher.
Following the example of ARM:
2cc0a7da87/lib/Target/ARM/ARMInstrInfo.td (L550-L555)
we introduce a new operand type to capture this list, and we use the
same {} syntax as ARM as well to differentiate them from regular
integer operands.
Also removed definition and use of TSFlags in tablegen defs, since
`br_table` now has a non-variable_ops immediate operand, so the
previous logic of only the variable_ops arguments being labels didn't
make sense anymore.
Reviewers: dschuff, aheejin, sunfish
Subscribers: javed.absar, sbc100, jgravelle-google, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D55401
llvm-svn: 349405
Summary:
This patch supports `.eventtype` directive printing and parsing in the
same syntax with `.functype`.
Reviewers: aardappel, sbc100
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55353
llvm-svn: 348818
Summary:
- Unify mixed argument names (`Symbol` and `Sym`) to `Sym`
- Changed `MCSymbolWasm*` argument of `emit***` functions to `const
MCSymbolWasm*`. It seems not very intuitive that emit function in the
streamer modifies symbol contents.
- Moved empty function bodies to the header
- clang-format
Reviewers: aardappel, dschuff, sbc100
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55347
llvm-svn: 348816
Summary:
- LLVM clang-format style doesn't allow one-line ifs.
- LLVM clang-tidy style says method names should start with a lowercase
letter. But currently WebAssemblyAsmParser's parent class
MCTargetAsmParser is mixing lowercase and uppercase method names
itself so overridden methods cannot be renamed now.
- Changed else ifs after returns to ifs.
- Added some newlines for readability.
Reviewers: aardappel, sbc100
Subscribers: dschuff, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55350
llvm-svn: 348648
Adds fatal errors for any target that does not support the Tiny or Kernel
codemodels by rejigging the getEffectiveCodeModel calls.
Differential Revision: https://reviews.llvm.org/D50141
llvm-svn: 348585
Summary:
The assembler processes directives and instructions in whatever order
they are in the file, then directly emits them to the streamer. This
could cause badly written (or generated) .s files to produce
incorrect binaries.
It now has state that tracks what it has most recently seen, to
enforce they are emitted in a given order that always produces
correct wasm binaries.
Also added a new test that compares obj2yaml output from llc (the
backend) to that going via .s and the assembler to ensure both paths
generate the same binaries.
The features this test covers could be extended.
Passes all wasm Lit tests.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=39557
Reviewers: sbc100, dschuff, aheejin
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55149
llvm-svn: 348185
Summary:
Expands for vector types all of the integer operations that are
expanded for scalars because they are not supported at all by
WebAssembly.
This CL has no tests because such tests would really be testing the
target-independent expansion, but I'm happy to add tests if reviewers
think it would be helpful.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55010
llvm-svn: 347923
Rather than assuming that `tempRet0` exists in linear memory only assume
the getter/setter functions exist. This avoids conflicting with
binaryen which declares a wasm global for this purpose and defines it's
own getter and setter for that.
The other advantage of doing things this way is that it leaving
it up to the linker/finalizer to decide how to actually store this
temporary. As it happens binaryen uses a wasm global which is more
appropriate since it is thread safe.
This also allows us to change the way this is stored in the future
(memory, TLS memory, wasm global) without modifying LLVM.
This is part of a 4 part change:
LLVM: https://reviews.llvm.org/D53240
fastcomp: https://github.com/kripken/emscripten-fastcomp/pull/237
emscripten: https://github.com/kripken/emscripten/pull/7358
binaryen: https://github.com/WebAssembly/binaryen/pull/1709
Differential Revision: https://reviews.llvm.org/D53240
llvm-svn: 347340
Summary:
This makes it easier/cleaner to generate a single signature from
this directive. Also:
- Adds the symbol name, such that we don't depend on the location
of this directive anymore.
- Actually constructs the signature in the assembler, and make the
assembler own it.
- Refactor the use of MVT vs ValType in the streamer and assembler
to require less conversions overall.
- Changed 700 or so tests to use it.
Reviewers: sbc100, dschuff
Subscribers: jgravelle-google, eraman, aheejin, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D54652
llvm-svn: 347228
Summary:
`throw` instruction is a terminator in wasm, but BBs were not splitted
after `throw` instructions, causing machine instruction verifier to
fail.
This patch
- Splits BBs after `throw` instructions in WasmEHPrepare and adding an
unreachable instruction after `throw`, which will be deleted in
LateEHPrepare pass
- Refactors WasmEHPrepare into two member functions
- Changes the semantics of `eraseBBsAndChildren` in LateEHPrepare pass
to match that of WasmEHPrepare pass, which is newly added. Now
`eraseBBsAndChildren` does not delete BBs with remaining predecessors.
- Fixes style nits, making static function names conform to clang-tidy
- Re-enables the test temporarily disabled by rL346840 && rL346845
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54571
llvm-svn: 347003
Summary:
The old return type did not allow for correct error reporting and was
causing a compiler warning.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54586
llvm-svn: 346979
Summary:
This adds support for the 'event section' specified in the exception
handling proposal. (This was named 'exception section' first, but later
renamed to 'event section' to take possibilities of other kinds of
events into consideration. But currently we only store exception info in
this section.)
The event section is added between the global section and the export
section. This is for ease of validation per request of the V8 team.
This patch:
- Creates the event symbol type, which is a weak symbol
- Makes 'throw' instruction take the event symbol '__cpp_exception'
- Adds relocation support for events
- Adds WasmObjectWriter / WasmObjectFile (Reader) support
- Adds obj2yaml / yaml2obj support
- Adds '.eventtype' printing support
Reviewers: dschuff, sbc100, aardappel
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54096
llvm-svn: 346825
Summary:
This is to replace the ELFAsmParser that WebAssembly was using, which
so far was a stub that didn't do anything, and couldn't work correctly
with wasm.
This new class is there to implement generic directives related to
wasm as a binary format. Wasm target specific directives are still
parsed in WebAssemblyAsmParser as before. The two classes now
cooperate more correctly too.
Also implemented .result which was missing. Any unknown directives
will now result in errors.
Reviewers: dschuff, sbc100
Subscribers: mgorny, jgravelle-google, eraman, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54360
llvm-svn: 346700
Summary:
Reorders the sections in the SIMD tablegen file to roughly match the
new opcode ordering. Depends on D54126.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54134
llvm-svn: 346464
Summary:
The pass incorrectly assumed if there's a longjmp declaration in the
module, there is also a setjmp function declaration. Fixed it, and now
the pass only converts longjmp and does not do any other transformation
when there's no setjmp declaration in the module.
Fixes PR39562.
Reviewers: jgravelle-google, sbc100
Subscribers: dschuff, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54273
llvm-svn: 346445
This reverts rL345880. It caused some test failures on the
webassembly waterfall. e.g. binaryen2.test_mainenv fails due
the fact that `envp` ends up being undef rather than 0.
Differential Revision: https://reviews.llvm.org/D54117
llvm-svn: 346187
Summary:
The assembler was able to assemble and then dump back to .s, but
was failing to parse certain directives necessary for valid .o
output:
- .type directives are now recognized to distinguish function symbols
and others.
- .size is now parsed to provide function size.
- .globaltype (introduced in https://reviews.llvm.org/D54012) is now
recognized to ensure symbols like __stack_pointer have a proper type
set for both .s and .o output.
Also added tests for the above.
Reviewers: sbc100, dschuff
Subscribers: jgravelle-google, aheejin, dexonsmith, kristina, llvm-commits, sunfish
Differential Revision: https://reviews.llvm.org/D53842
llvm-svn: 346047
Summary:
EH stack depth is incremented at `try` and decremented at `catch`. When
there are more than two catch instructions for a try instruction, we
shouldn't count non-first catches when calculating EH stack depths.
This patch fixes two bugs:
- CFGStackify: Exclude `catch_all` in the terminate catch pad when
calculating EH pad stack, because when we have multiple catches for a
try we should count only the first catch instruction when calculating
EH pad stack.
- InstPrinter: The initial intention was also to exclude non-first
catches, but it didn't account nested try-catches, so it failed on
this case:
```
try
try
catch
end
catch <-- (1)
end
```
In the example, when we are at the catch (1), the last seen EH
instruction is not `try` but `end_try`, violating the wrong assumption.
We don't need these after we switch to the second proposal because there
is gonna be only one `catch` instruction. But anyway before then these
bugfixes are necessary for keep trunk in working state.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53819
llvm-svn: 346029
Summary:
Assembly output can use globals like __stack_pointer implicitly,
but has no way of indicating the type of such a global, which makes
it hard for tools processing it (such as the MC Assembler) to
reconstruct this information.
The improved assembler directives parsing (in progress in
https://reviews.llvm.org/D53842) will make use of this information.
Also deleted code for the .import_global directive which was unused.
New test case in userstack.ll
Reviewers: dschuff, sbc100
Subscribers: jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54012
llvm-svn: 345917
Summary:
Like `block` or `loop`, `try` can take an optional signature which can
be omitted. This patch allows `try`'s signature to be omitted. Also
added some tests for EH instructions.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53873
llvm-svn: 345888
This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
of only 'break'.
We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
the outer case.
I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.
Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu
Differential Revision: https://reviews.llvm.org/D53950
llvm-svn: 345882
Summary:
Also reduce the test case for implicit defs and test it with all
register classes.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53855
llvm-svn: 345794
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.
In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)
This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer
Reviewers: dschuff, sbc100, rnk
Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52748
llvm-svn: 345345
Summary:
Currently InstPrinter ignores if there are mismatches between block/loop
and end markers by skipping the case if ControlFlowStack is empty. I
guess it is better to explicitly error out in this case, because this
signals invalid input.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53620
llvm-svn: 345333
Summary: Fixes part of the problem reported in bug 39275.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits, alexcrichton
Differential Revision: https://reviews.llvm.org/D53542
llvm-svn: 345230
Summary:
Currently when assigning depths 'rethrow' does not take the whole
control flow stack into accounts but only considers EH pad stacks. When
assigning depth immmediates to rethrows, in normal cases it is done
correctly but when a rethrow instruction throws up to a caller, i.e., we
convert a pseudo RETHROW_TO_CALLER instruction to a rethrow, it
mistakenly compute the whole stack depth.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53619
llvm-svn: 345223
Summary:
Changing the node type in lowering was violating assumptions made in
the DAG combiner, so don't change the node type any more. This fixes
one of the issues reported in bug 39275.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits, alexcrichton
Differential Revision: https://reviews.llvm.org/D53537
llvm-svn: 345221
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.
Reviewers: arsenm, aheejin, dschuff, javed.absar
Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits
Differential Revision: https://reviews.llvm.org/D53112
llvm-svn: 345218
Vector types are not possible here because this code explicitly
checks for a scalar type, but this is another step towards
completely removing the fake binop queries for not/neg/fneg.
llvm-svn: 345043
Summary:
Replace its functionality with a TableGen InstrInfo relational
instruction mapping. Although arguably more complex than the TableGen
backend, the relational mapping is a smaller maintenance burden than a
TableGen backend.
Reviewers: aardappel, aheejin, dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53307
llvm-svn: 344962
Summary:
Undefined indices in shuffles can be used when not all lanes of the
output vector will be used. This happens for example in the expansion
of vector reduce operations. Regardless, undefs are legal as lane
indices in IR and should be supported.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53057
llvm-svn: 344803
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.
In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)
This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer
Reviewers: dschuff, sbc100, rnk
Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52748
llvm-svn: 344575
by `getTerminator()` calls instead be declared as `Instruction`.
This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).
llvm-svn: 344502
Summary:
Although the saturating float to int instructions are already
emitted from normal IR, the fpto{s,u}i instructions produce poison
values if the argument cannot fit in the result type. These intrinsics
are therefore necessary to get guaranteed defined saturating behavior.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53004
llvm-svn: 344204
Summary:
By moving that line into the `I` multiclass.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53093
llvm-svn: 344180
Summary:
Subtraction from zero and floating point negation do not have the same
semantics, so fix lowering.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52948
llvm-svn: 344107
Summary:
Also add tests to catch crashes in passes that are not normally run in
tests.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52959
llvm-svn: 344094
Summary:
- Categorize instructions into the categories as in the SIMD spec
- Move SIMD-related definition to WebAssemblyInstrSIMD.td
- Put definition and use of patterns together
- Add newlines here and there
Reviewers: tlively
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53045
llvm-svn: 344086
Summary:
Fixes https://bugs.llvm.org/show_bug.cgi?id=39158 and regression caused by
D49034. Though it is possible the problem was existed before and was exposed by
additional DBG_VALUEs.
Reviewers: sunfish, dschuff, aheejin
Reviewed By: aheejin
Subscribers: sbc100, aheejin, llvm-commits, alexcrichton, jgravelle-google
Differential Revision: https://reviews.llvm.org/D52837
llvm-svn: 343827
MCContext does not destroy MCSymbols on shutdown. So, rather than putting
SmallVectors (which may heap-allocate) inside MCSymbolWasm, use unowned pointer
to a WasmSignature instead. The signatures are now owned by the AsmPrinter.
Also uses WasmSignature instead of param and result vectors in TargetStreamer,
and leaves some TODOs for further simplification.
Differential Revision: https://reviews.llvm.org/D52580
llvm-svn: 343733
Previously we were creating weakly defined helper function in
each translation unit:
- setThrew
- setTempRet0
Instead we now assume these will be provided at link time. In
emscripten they are provided in compiler-rt:
https://github.com/kripken/emscripten/pull/7203
Additionally we previously created three global variable which are
also now required to exist at link time instead.
- __THREW__
- _threwValue
- __tempRet0
Differential Revision: https://reviews.llvm.org/D49208
llvm-svn: 343640
Summary:
The AsmParser Lexer regards these as a seperate token.
Here we expand the instruction name with them if they are
adjacent (no whitespace).
Tested: the basic-assembly.s test case has one case with a / in it.
The currently are also instructions with : in them, which we intend
to rename rather than fix them here.
Reviewers: tlively, dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52442
llvm-svn: 343501
Summary:
The OneUseDominatesOtherUses in the WebAssemblyRegStackify not properly validates register use using hasOneUse. Since we added/modified DBG_VALUE the assert started catching valid cases.
See also https://reviews.llvm.org/D49034#1247200
Fix verified by running the wasm waterfall.
Reviewed By: dschuff
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D49034
llvm-svn: 343154
Summary:
Lowers (s|u)itofp and fpto(s|u)i instructions for vectors. The fp to
int conversions produce poison values if their arguments are out of
the convertible range, so a future CL will have to add an LLVM
intrinsic to make the saturating behavior of this conversion usable.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52372
llvm-svn: 343052
Summary:
By using the existing isCodeGenOnly bit in the tablegen defs, as
suggested by tlively in https://reviews.llvm.org/D51662
Tested: llvm-lit -v `find test -name WebAssembly`
Reviewers: tlively
Subscribers: dschuff, sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52373
llvm-svn: 342772
Summary: Adds the necessary support to lib/ObjectYAML and fixes SIMD
calls to allow the tests to work. Also removes some dead code that
would otherwise have to have been updated.
Reviewers: aheejin, dschuff, sbc100
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52105
llvm-svn: 342689
Summary:
This change leaves holes in the opcode space where missing
instructions could logically be added later if they were found to be
useful.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52282
llvm-svn: 342610
Summary:
Implement shifts of vectors by i32. Since LLVM defines shifts as
binary operations between two vectors, this involves pattern matching
on splatted shift operands. For v2i64 shifts any i32 shift operands
have to be zero extended in the input and any i64 shift operands have
to be wrapped in the output. Depends on D52007.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51906
llvm-svn: 342302
Also, add a check to ensure that when main has the expected signature
we do not create a wrapper.
Differential Revision: https://reviews.llvm.org/D51562
llvm-svn: 342157
Summary:
rL341389 broke code with tied register operands in inline assembly. For
example, `asm("" : "=r"(var) : "0"(var));`
The code above specifies the input operand to be in the same register
with the output operand, tying the two register. This patch makes this
kind of code work again.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, eraman, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51991
llvm-svn: 342084
Summary:
Match the ordering semantics of non-vector comparisons. For
floating point comparisons that do not correspond to instructions, the
tests check that some vector comparison instruction was emitted but do
not care about the full implementation.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51765
llvm-svn: 342064
Disassemblers cannot depend on main target headers. The same is true for
MCTargetDesc, but there's a lot more cleanup needed for that.
llvm-svn: 341822
Summary:
Since the shuffle mask is not exposed as an operand in the native ISel
DAG, create a new WebAssembly ISD node exposing the mask. The mask is
lowered as sixteen immediate byte indices no matter what type the
original vector shuffle was operating on.
This CL depends on D51656
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51659
llvm-svn: 341718
Summary: To explicitly opt out of LEB encoding for these immediates.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51766
llvm-svn: 341707
Use MachineOperand::ChangeToImmediate rather than reassigning
MachineOperands to new values created from MachineOperand::CreateImm,
so that their parent pointers are preserved.
This fixes "Instruction has operand with wrong parent set" errors
reported by the MachineVerifier.
llvm-svn: 341389
Summary:
Now uses the StackBased bit from the tablegen defs to identify
stack instructions (and ignore register based or non-wasm instructions).
Also changed how we store operands, since we now have up to 16 of them
per instruction. To not cause static data bloat, these are compressed
into a tiny table.
+ a few other cleanups.
Tested:
- MCTest
- llvm-lit -v `find test -name WebAssembly`
Reviewers: dschuff, jgravelle-google, sunfish, tlively
Subscribers: sbc100, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D51320
llvm-svn: 341081
We don't have enough information to know if struct types being
bitcast will cause validation failures or not, so be conservative
and allow such cases to persist (fot now).
Fixes: https://bugs.llvm.org/show_bug.cgi?id=38711
Subscribers: dschuff, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51460
llvm-svn: 341010
Summary:
Add comments to help readers avoid having to read tablegen backends to
understand the code. Also remove unecessary breaks from the output.
Reviewers: dschuff, aheejin
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51371
llvm-svn: 340864
Summary:
The new stackification backend generates the giant switch statement
used to translate instructions to their stackified forms. I did this
because it was more interesting than adding all the different vector
versions of the various SIMD instructions to the switch statment
manually.
Reviewers: aardappel, aheejin, dschuff
Subscribers: mgorny, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D51318
llvm-svn: 340781
Summary:
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll
tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*
Reviewers: dschuff, sunfish
Subscribers: sbc100, jgravelle-google, eraman, aheejin, llvm-commits, jfb
Differential Revision: https://reviews.llvm.org/D51241
llvm-svn: 340750
Summary:
Splats are fewer bytes than v128.consts, so use them when either could
apply.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51179
llvm-svn: 340569
Summary:
Reorganize WebAssemblyInstrSIMD.td to put all of the instruction
definitions together, making it easier to see which instructions have
been implemented already. Depends on D51143.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51113
llvm-svn: 340504
Summary:
WebAssemblyInstrFormats.td retains only multiclasses that are used in
multiple other tablegen files.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D51143
llvm-svn: 340503
Summary:
This CL adds support for arbitrary BUILD_VECTORS, i.e. not splats and
not consts. This is the last feature needed to properly lower v2i64
multiplies without a i64x2.mul instruction (which is not in the spec),
so i64x2.mul is removed as well.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51082
Remove unnecessary condition and fix whitespace
llvm-svn: 340472
Summary:
When we don't actually have stack-allocated variables but need SP only
to support EH, we don't need to write SP back in the epilog, because we
don't bump down the stack pointer.
Reviewers: dschuff
Subscribers: jgravelle-google, sbc100, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51114
llvm-svn: 340454
Summary:
There are several functions in the form of `has***` or `needs***` in
`WebAssemblyFrameLowering` and its `MachineFrameInfo` argument can be
obtained from `MachineFunction` so it is not necessarily has to be
passed from a caller. Also, it is more in line with other overriden
fuctions like `hasBP` or `hasReservedCallFrame`, which also take only
`MachineFunction` argument.
Reviewers: dschuff
Subscribers: sbc100, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51116
llvm-svn: 340438
Summary:
`catch` instruction certainly has rather huge side effects and the flag
was missing. At the moment this does not change any unit tests we
currently have.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50919
llvm-svn: 340433
Summary: We now write back not to memory but to __stack_pointer global.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51074
llvm-svn: 340372
Summary:
After the stack is unwound due to a thrown exception, the
`__stack_pointer` global can point to an invalid address. This inserts
instructions that restore `__stack_pointer` global.
Reviewers: jgravelle-google, dschuff
Subscribers: mgorny, sbc100, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50980
llvm-svn: 340339
Summary:
This CL implements v128.const for each vector type. New operand types
are added to ensure the vector contents can be serialized without LEB
encoding. Tests are added for instruction selection, encoding,
assembly and disassembly.
Reviewers: aheejin, dschuff, aardappel
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50873
llvm-svn: 340336
Summary: SP is now a __stack_pointer global and not a memory address anymore.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D51046
llvm-svn: 340328
Summary:
So far, `isReturn` property is used to mean both a return instruction
from a functon and the end of an EH scope, a scope that starts with a EH
scope entry BB and ends with a catchret or a cleanupret instruction.
Because WinEH uses funclets, all EH-scope-ending instructions are also
real return instruction from a function. But for wasm, they only serve
as the end marker of an EH scope but not a return instruction that
exits a function. This mismatch caused incorrect prolog and epilog
generation in wasm EH scopes. This patch fixes this.
This patch is in the same vein with rL333045, which splits
`MachineBasicBlock::isEHFuncletEntry` into `isEHFuncletEntry` and
`isEHScopeEntry`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50653
llvm-svn: 340325
Summary:
We decided to revert this from i64 to i32 in Nov 28 CG meeting. Fixes
PR38632.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D51010
llvm-svn: 340234
Summary:
This adds support for exception handling to CFGStackify pass. This only
adds TRY / END_TRY markers and DOES NOT yet fix unwind mismatches that
can be created by the linearization of the CFG into the structural wasm
format. The mismatch fix will be added by following patches.
In detail, this patch
- Added support for TRY / END_TRY markers to support EH
- Changed many static functions into class member functions as they take
too many arguments now
- Added several more bookeeping data structures
- Refactored routines that decide where to insert markers, because
without refactoring this got too complicated as we added support for new
kinds of markers (TRY/END_TRY).
- Rewrote rethrow instructions' BB arguments to relative depths in EH
pad stack.
Reviewers: dschuff, sunfish
Subscribers: sbc100, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D48273
llvm-svn: 339967
Summary:
EM_ASM no longer is lowered as varargs in C, so this workaround is
obsolete.
Reviewers: dschuff, sunfish
Subscribers: sbc100, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D50859
llvm-svn: 339925
Summary:
This CL changes the ExtractLane ISEL multiclass to more closely mirror
the structure of the splat and replace_lane multiclasses.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50794
llvm-svn: 339801
Previously SIMD_I was the same as a normal instruction except for the
addition of a HasSIM128 predicate. However, rL339186 changed the
encoding of SIMD_I instructions to automatically contain the SIMD
prefix byte. This broke the encoding of non-SIMD vector-typed
instructions, which had instantiated SIMD_I. This CL corrects this
error.
Reviewers: aheejin
Subscribers: sunfish, jgravelle-google, sbc100, llvm-commits
Differential Revision: https://reviews.llvm.org/D50682
Patch by Thomas Lively (tlively)
llvm-svn: 339710
Implement instruction selection for all versions of the extract_lane
instruction. Use explicit sext/zext to differentiate between
extract_lane_s and extract_lane_u for applicable types, otherwise
default to extract_lane_u.
Reviewers: aheejin
Subscribers: sunfish, jgravelle-google, sbc100, llvm-commits
Differential Revision: https://reviews.llvm.org/D50597
Patch by Thomas Lively (tlively)
llvm-svn: 339707
Treat the stack variants of control instructions the same as regular
instructions. Otherwise, the vector ControlFlowStack will be the wrong
size and have out-of-bounds access. This was detected by MemorySanitizer.
llvm-svn: 339495
Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll
tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*
Reviewers: dschuff, sunfish
Subscribers: jfb, llvm-commits, aheejin, eraman, jgravelle-google, sbc100
Differential Revision: https://reviews.llvm.org/D50568
llvm-svn: 339474
Summary:
i64x2 and f64x2 operations are not implemented in V8, so we normally
do not want to emit them. However, they are in the SIMD spec proposal,
so we still want to be able to test them in the toolchain. This patch
adds a flag to enable their emission.
Reviewers: aheejin, dschuff
Subscribers: sunfish, jgravelle-google, sbc100, llvm-commits
Differential Revision: https://reviews.llvm.org/D50423
Patch by Thomas Lively (tlively)
llvm-svn: 339407
Summary:
gcc does not like
const Region *Region;
It wants a different name for the variable.
Is there a better convention for what name to use in such a case?
Reviewers: sbc100, aheejin
Subscribers: aheejin, jgravelle-google, dschuff, llvm-commits
Differential Revision: https://reviews.llvm.org/D50472
Patch by Alon Zakai (kripken)
llvm-svn: 339398
Add missing SIMD types (v2f64) and binary ops. Also adds
tablegen support for automatically prepending prefix byte to SIMD
opcodes.
Differential Revision: https://reviews.llvm.org/D50292
Patch by Thomas Lively
llvm-svn: 339186
Summary:
This patch extends CFGSort pass to support exception handling. Once it
places a loop header, it does not place blocks that are not dominated by
the loop header until all the loop blocks are sorted. This patch extends
the same algorithm to exception 'catch' part, using the information
calculated by WebAssemblyExceptionInfo class.
Reviewers: dschuff, sunfish
Subscribers: sbc100, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D46500
llvm-svn: 339172
Summary:
Wasm does not have direct counterparts to some of LLVM IR's atomicrmw
instructions (min, max, umin, umax, and nand). This enables atomic
expansion using cmpxchg instruction within a loop for those atomicrmw
instructions.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D49440
llvm-svn: 339084
Summary:
The spec only defines a SIMD expression type of V128 and
leaves interpretation of different vector types to the instructions.
Differential Revision: https://reviews.llvm.org/D50367
Patch by Thomas Lively
llvm-svn: 339082
Rather than allowing invalid bitcasts to be lowered to wasm
call instructions that won't validate, generate wrappers that
contain unreachable thereby delaying the error until runtime.
Differential Revision: https://reviews.llvm.org/D49517
llvm-svn: 338744
Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll
tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*
Reviewers: dschuff, sunfish
Subscribers: sbc100, jgravelle-google, eraman, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D49160
llvm-svn: 338164
When building with LTO, builtin functions that are defined but whose calls have not been inserted yet, get internalized. The Global Dead Code Elimination phase in the new LTO implementation then removes these function definitions. Later optimizations add calls to those functions, and the linker then dies complaining that there are no definitions. This CL fixes the new LTO implementation to check if a function is builtin, and if so, to not internalize (and later DCE) the function. As part of this fix I needed to move the RuntimeLibcalls.{def,h} files from the CodeGen subidrectory to the IR subdirectory. I have updated all the files that accessed those two files to access their new location.
Fixes PR34169
Patch by Caroline Tice!
Differential Revision: https://reviews.llvm.org/D49434
llvm-svn: 337847
Summary:
lifetime2.C violates DR1696, which prevents reference members from being
initialized to temporaries, whose lifetime would end at the end of ctor.
Reviewers: sbc100
Subscribers: dschuff, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D49577
llvm-svn: 337512
Summary:
The use of exception handling instructions should only be enabled with
`-mattr=+exception-handling` option.
Reviewers: jgravelle-google
Subscribers: dschuff, sbc100, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D49391
llvm-svn: 337425
Previously we were assuming whole program compilation. Now that
separate compilation is a thing we need to update this pass.
Firstly, it can no longer assert on the existence of malloc and free.
This functions might not be in the current translation unit. If we
need them then we will generate not imports for them.
Secondly the global helper function we create should be marked as
weak since we will be generating a separate copy in each translation
unit.
Finally the names of the symbols used must be unique and fixed since
they need to agree across translation units.
Differential Revision: https://reviews.llvm.org/D49263
llvm-svn: 337301
This support was partial and temporary. Now that we have
wasm object file support its no longer needed.
Differential Revision: https://reviews.llvm.org/D48744
llvm-svn: 337222
Summary:
This adds support for binary atomic read-modify-write instructions:
add, sub, and, or, xor, and xchg.
This does not yet support translations of some of LLVM IR atomicrmw
instructions (nand, max, min, umax, and umin) that do not have a direct
counterpart in wasm instructions.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D49088
llvm-svn: 336615
Summary:
- Changed variable/function names to be more consistent
- Improved comments in test files
- Added more tests
- Fixed a few typos
- Misc. cosmetic changes
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D49087
llvm-svn: 336598
LLVM doesn't guarantee anything about the high bits of a register holding
an i1 value at the IR level, so don't translate LLVM IR i1 values directly
into WebAssembly conditional branch operands. WebAssembly's conditional
branches do demand all 32 bits be valid.
Fixes PR38019.
llvm-svn: 336138
CallLoweringInfo's NumFixedArgs field gives the number of fixed arguments
before legalization. The ISD::OutputArg "Outs" array holds legalized
arguments, so when indexing into it to find the non-fixed arguemn, we need
to use the number of arguments after legalization.
Fixes PR37934.
llvm-svn: 335576
Summary:
A WebAssemblyException object contains BBs that belong to a 'catch' part
of the try-catch-end structure. Because CFGSort requires all the BBs
within a catch part to be sorted together as it does for loops, this
pass calculates the nesting structure of catch part of exceptions in a
function. Now this assumes the use of Windows EH instructions.
Reviewers: dschuff, majnemer
Subscribers: jfb, mgorny, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D44134
llvm-svn: 335439
Summary:
Add WebAssemblyLateEHPrepare pass that does several small jobs for
exception handling. This runs before CFGSort, and is different from
WasmEHPrepare pass that runs before ISel, even though the names are
similar.
Reviewers: dschuff, majnemer
Subscribers: sbc100, jgravelle-google, sunfish, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D46803
llvm-svn: 335438
Summary:
The waterfall no longer builds .s files and no longers uses
the wasm-o when it builds object files.
Subscribers: dschuff, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D48371
llvm-svn: 335135
Summary:
This fixes liveness tracking information after `drop` instruction
insertion in ExplicitLocals pass.
When a drop instruction is inserted to drop a dead register operand, the
original operand should be marked not dead anymore because it is now
used by the new drop instruction. And the operand to the new drop
instruction should be marked killed instead. This bug caused some
programs to fail when `llc` is run with `-verify-machineinstrs` option.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D48253
llvm-svn: 335074
Summary:
Added more utility functions that will be used in EH-related passes Also
changed `LoopBottom` function to `getBottom` and uses templates to be
able to handle other classes as well, which will be used in CFGSort
later.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D48262
llvm-svn: 335006
Summary:
This patch changes the rethrow instruction to take a BB argument in LLVM
backend, like `br` and `br_if`s. This BB is a target catch BB the
rethrow instruction unwinds to. This BB argument will be converted to an
relative depth immediate at the end of CFGStackify pass, as in the same
way of branches.
RETHROW_TO_CALLER is a codegen-only instruction that should be used when
a rethrow instruction does not have an unwind destination BB, i.e., it
should rethrow to its caller function.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D48260
llvm-svn: 334998
Summary:
One for register based, much like the existing definitions,
and one for stack based (suffix _S).
This allows us to use registers in most of LLVM (which works better),
and stack based in MC (which results in a simpler and more readable
assembler / disassembler).
Tried to keep this change as small as possible while passing tests,
follow-up commit will:
- Add reg->stack conversion in MI.
- Fix asm/disasm in MC to be stack based.
- Fix emitter to be stack based.
tests passing:
llvm-lit -v `find test -name WebAssembly`
test/CodeGen/WebAssembly
test/MC/WebAssembly
test/MC/Disassembler/WebAssembly
test/DebugInfo/WebAssembly
test/CodeGen/MIR/WebAssembly
test/tools/llvm-objdump/WebAssembly
Reviewers: dschuff, sbc100, jgravelle-google, sunfish
Subscribers: aheejin, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D48183
llvm-svn: 334985
The ELF version was broken (does not deal with wasm specific fixups),
and now is slightly less broken. It will be removed in its entirety
in the future which this change makes slightly easier (just remove
the IsELF bool).
Differential Revision: https://reviews.llvm.org/D47745
Patch by Wouter van Oortmerssen
llvm-svn: 333964
The WebAssembly committee has decided on the names `memory.size` and
`memory.grow` for the memory intrinsics, so update the LLVM intrinsics to
follow those names, keeping both sets of old names in place for
compatibility.
llvm-svn: 333708
Summary:
This lowers exception catching-related instructions:
1. Lowers `wasm.catch` intrinsic to `catch` instruction
2. Removes `catchpad` and `cleanuppad` instructions; they are not
necessary after isel phase. (`MachineBasicBlock::isEHFuncletEntry()` or
`MachineBasicBlock::isEHPad()` can be used instead.)
3. Lowers `catchret` and `cleanupret` instructions to pseudo `catchret`
and `cleanupret` instructions in isel, which will be replaced with other
instructions in `WebAssemblyExceptionPrepare` pass.
4. Adds 'WebAssemblyExceptionPrepare` pass, which is for running various
transformation for EH. Currently this pass only replaces `catchret` and
`cleanupret` instructions into appropriate wasm instructions to make
this patch successfully run until the end.
Currently this does not handle lowering of intrinsics related to LSDA
info generation (`wasm.landingpad.index` and `wasm.lsda`), because they
cannot be tested without implementing `EHStreamer`'s wasm-specific
handlers. They are marked as TODO, which is needed to make isel pass.
Also this does not generate `try` and `end_try` markers yet, which will
be handled in later patches.
This patch is based on the first wasm EH proposal.
(https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md)
Reviewers: dschuff, majnemer
Subscribers: jfb, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D44090
llvm-svn: 333705
For both argument and return types, promote illegal types like i24 to i32,
and if a type can't be easily promoted, clear out the signature before
bailing out, so avoid leaving it in a partially complete state.
Fixes PR37546.
llvm-svn: 332947
With this we gain a little flexibility in how the generic object
writer is created.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47045
llvm-svn: 332868
To make this work I needed to add an endianness field to MCAsmBackend
so that writeNopData() implementations know which endianness to use.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47035
llvm-svn: 332857
Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47032
llvm-svn: 332757
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
This implements a new table-gen emitter to create tables for
a wasm disassembler, and a dissassembler to use them.
Comes with 2 tests, that tests a few instructions manually. Is also able to
disassemble large .wasm files with objdump reasonably.
Not working so well, to be addressed in followups:
- objdump appears to be passing an incorrect starting point.
- since the disassembler works an instruction at a time, and it is
disassembling stack instruction, it has no idea of pseudo register assignments.
These registers are required for the instruction printing code that follows.
For now, all such registers appear in the output as $0.
Patch by Wouter van Oortmerssen
Differential Revision: https://reviews.llvm.org/D45848
llvm-svn: 332052
Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.
This patch has no new test case. I have run regression test and there is
no difference in regression test.
Differential Revision: https://reviews.llvm.org/D45342
Patch by Hsiangkai Wang.
llvm-svn: 331844
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
Summary:
It was not easy to provide a test case for D45648 (rL330079) because the bug
didn't manifest itself in the set of currently valid IRs. Added an assertion to
check this faster, thanks to @dblaikie's suggestion.
Reviewers: dblaikie
Subscribers: jfb, dschuff, sbc100, jgravelle-google, llvm-commits, dblaikie
Differential Revision: https://reviews.llvm.org/D45711
llvm-svn: 330217
Summary:
InsertPos is within the bacic block `Header`, so `findDebugLoc()` should
be called on not `MBB` but `Header` instead.
Reviewers: yurydelendik
Subscribers: jfb, dschuff, aprantl, sbc100, jgravelle-google, sunfish, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D45648
llvm-svn: 330079
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.
Reviewers: sunfish, RKSimon
Reviewed By: sunfish
Subscribers: jfb, dschuff, sbc100, jgravelle-google, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D44873
llvm-svn: 329607
This patch adds a way for users to create their own custom sections to
be added to wasm files. At the LLVM IR layer, they are defined through
the "wasm.custom_sections" named metadata. The expected use case for
this is bindings generators such as wasm-bindgen.
Patch by Dan Gohman
Differential Revision: https://reviews.llvm.org/D45297
llvm-svn: 329315
A bug was found where an offset of -1 would generate an encoding
of max int64 which is invalid in the binary format.
Differential Revision: https://reviews.llvm.org/D45280
llvm-svn: 329238
Makes it easier to see mistakes such as the one fixed in r329178 and makes
the different target CMakeLists more consistent.
Also remove some stale-looking comments from the Nios2 target cmakefile.
No intended behavior change.
llvm-svn: 329181
Summary:
This change declare that PostRAMachineSinking and ShrinkWrap require NoVRegs
property, so now the MachineFunctionPass can enforce this check.
These passes are disabled in NVPTX & WebAssembly.
Reviewers: dschuff, jlebar, tra, jgravelle-google, MatzeB, sebpop, thegameg, mcrosier
Reviewed By: dschuff, thegameg
Subscribers: jholewinski, jfb, sbc100, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D45183
llvm-svn: 329095
Summary:
This exposes WebAssembly passes for use on the command line (as
arguments to -print-before and the like).
Reviewers: dschuff, sunfish
Subscribers: MatzeB, jfb, sbc100, llvm-commits, aheejin
Differential Revision: https://reviews.llvm.org/D45103
llvm-svn: 328901
This is used by llvm tblgen as well as by LLVM Targets, so the only
common place is Support for now. (maybe we need another target for these
sorts of things - but for now I'm at least making them correct & we can
make them better if/when people have strong feelings)
llvm-svn: 328395
The "ShouldEmitMatchRegisterName" bit wasn't taking effect because the
WebAssembly target didn't point to the custom WebAssemblyAsmParser
record.
llvm-svn: 328155
The default thread model for wasm is single, and in this mode thread-local
global variables can be lowered identically to non-thread-local variables.
Differential Revision: https://reviews.llvm.org/D44703
llvm-svn: 328049
It uses the MC framework and the tablegen matcher to do the
heavy lifting. Can handle both explicit and implicit locals
(-disable-wasm-explicit-locals). Comes with a small regression
test.
This is a first basic implementation that can parse most llvm .s
output and round-trips most instructions succesfully, but in order
to keep the commit small, does not address all issues.
There are a fair number of mismatches between what MC / assembly
matcher think a "CPU" should look like and what WASM provides,
some already have workarounds in this commit (e.g. the way it
deals with register operands) and some that require further work.
Some of that further work may involve changing what the
Disassembler outputs (and what s2wasm parses), so are probably
best left to followups.
Some known things missing:
- Many directives are ignored and not emitted.
- Vararg calls are parsed but extra args not emitted.
- Loop signatures are likely incorrect.
- $drop= is not emitted.
- Disassembler does not output SIMD types correctly, so assembler
can't test them.
Patch by Wouter van Oortmerssen
Differential Revision: https://reviews.llvm.org/D44329
llvm-svn: 328028
This cast was causing invalid signatures to be written
for libcall functions.
Add an MC test which includes a call to builtin memcpy.
Differential Revision: https://reviews.llvm.org/D44037
llvm-svn: 326618
Summary:
Original change was D43991 (rL326541) and was reverted by rL326571 and
rL326572. This adds also the necessary MCCodeEmitter patch.
Reviewers: sbc100
Subscribers: jfb, dschuff, sbc100, jgravelle-google, sunfish, llvm-commits, ncw
Differential Revision: https://reviews.llvm.org/D44034
llvm-svn: 326614
This reverts commits r326541 and r326571.
The tests were correct, and were updated with incorrect expectations.
The original commit was broken and should be reverted to get things back
to a working state.
llvm-svn: 326572
Summary: It looks like this was missing from D43921.
Reviewers: sbc100
Subscribers: jfb, dschuff, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D43991
llvm-svn: 326541
Summary:
- Gather EH instructions in one place for easy tracking (more will be
added later)
- Variable name change
Reviewers: dschuff
Subscribers: jfb, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D43742
llvm-svn: 326522
The original BinaryEncoding.md document used to specify that
these values were `varint7`, but the official spec lists them
explicitly as single byte values and not LEB.
A similar change for wabt is in flight:
https://github.com/WebAssembly/wabt/pull/782
Differential Revision: https://reviews.llvm.org/D43921
llvm-svn: 326454
This will still be constexpr when the standard library supports it, but
doesn't force constexpr. Old libraries will get a global constructor,
which is not too bad.
llvm-svn: 326080
This is combination of two patches by Nicholas Wilson:
1. https://reviews.llvm.org/D41954
2. https://reviews.llvm.org/D42495
Along with a few local modifications:
- One change I made was to add the UNDEFINED bit to the binary format
to avoid the extra byte used when writing data symbols. Although this
bit is redundant for other symbols types (i.e. undefined can be
implied if a function or global is a wasm import)
- I prefer to be explicit and consistent and not have derived flags.
- Some field renaming.
- Some reverting of unrelated minor changes.
- No test output differences.
Differential Revision: https://reviews.llvm.org/D43147
llvm-svn: 325860
Add an explicit check before looking up symbol in SymbolIndices.
This was previously silently succeeding and returning zero for such
unnamed temporaries.
Differential Revision: https://reviews.llvm.org/D43365
llvm-svn: 325367
Summary:
wasm32-unknown-unknown-elf has MCSymbols that are not MCSymbolWasms, so
we need a non-asserting cast here.
Reviewers: dschuff, sunfish
Subscribers: jfb, sbc100, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D43205
llvm-svn: 324942
This adds a wasm-import-module function attribute and a .import_module
assembler directive, for specifying module import names for WebAssembly.
Currently these may only be used for function symbols; global variables
may be considered in the future.
WebAssembly has a two-level namespace scheme for symbols, and it's
normally the linker's job to assign the module name, which is the
first-level name. The attributes here allow users to specify their
own module names explicitly, which is useful for tools generating
bindings to modules defined in other languages.
This feature is not fully usable yet. It will evolve along with the
ongoing symbol table and lld changes.
Differential Revision: https://reviews.llvm.org/D42520
llvm-svn: 324778
For now, we are not using wasm globals, except for modeling of
the stack points.
Alos, factor out common struct WasmGlobalType, which matches the
name for that tuple in the Wasm spec and rename methods
to "isBindingGlobal", "isTypeGlobal" to avoid ambiguity.
Patch by Nicholas Wilson!
Differential Revision: https://reviews.llvm.org/D42750
llvm-svn: 323901
Previously some targets printed their own message at the start of Select to indicate what they were selecting. For the targets that didn't, it means there was no print of the root node before any custom handling in the target executed. So if the target did something custom and never called SelectNodeCommon, no print would be made. For the targets that did print a message in Select, if they didn't custom handle a node SelectNodeCommon would reprint the root node before walking the isel table.
It seems better to just print the message before the call to Select so all targets behave the same. And then remove the root node printing from SelectNodeCommon and just leave a message that says we're starting the table search.
There were also some oddities in blank line behavior. Usually due to a \n after a call to SelectionDAGNode::dump which already inserted a new line.
llvm-svn: 323551
The grow_memory and current_memory instructions are expected to be
officially renamed to mem.grow and mem.size. Introduce new intrinsics
with the new names. These new names aren't yet official, so for now,
use them at your own risk.
Also, take this opportunity to add arguments for the currently unused
immediate field in those instructions.
llvm-svn: 323222
RuntimeLibcallSignatures previously manually initialized all the libcall
names into an array and searched it linearly for the first match to lookup
the corresponding index.
r322802 switched that to initializing a map keyed by the libcall name.
Neither of these approaches works correctly because some libcall numbers use
the same name on different platforms (e.g. the "l" suffixed functions
use f80 or f128 or ppcf128).
This change fixes that by ensuring that each name only goes into the map
once. It also adds tests.
Differential Revision: https://reviews.llvm.org/D42271
llvm-svn: 322971
Sign-extension opcodes have been split into a separate proposal from
the main threads proposal, so switch them to their own target
feature. See:
https://github.com/WebAssembly/sign-extension-ops
llvm-svn: 322966
Remove the tight coupling between llvm/CodeGenRuntimeLibcalls.def and
the table of supported singatures for wasm. This will allow adding new libcalls
without changing wasm's signature table.
Also, some cleanup:
Use ManagedStatics instead of const tables to avoid memory/binary bloat.
Use a StringMap instead of a linear search for name lookup.
Differential Revision: https://reviews.llvm.org/D35592
llvm-svn: 322802
Re-land r321234. It had to be reverted because it broke the shared
library build. The shared library build broke because there was a
missing LLVMBuild dependency from lib/Passes (which calls
TargetMachine::getTargetIRAnalysis) to lib/Target. As far as I can
tell, this problem was always there but was somehow masked
before (perhaps because TargetMachine::getTargetIRAnalysis was a
virtual function).
Original commit message:
This makes the TargetMachine interface a bit simpler. We still need
the std::function in TargetIRAnalysis to avoid having to add a
dependency from Analysis to Target.
See discussion:
http://lists.llvm.org/pipermail/llvm-dev/2017-December/119749.html
I avoided adding all of the backend owners to this review since the
change is simple, but let me know if you feel differently about this.
Reviewers: echristo, MatzeB, hfinkel
Reviewed By: hfinkel
Subscribers: jholewinski, jfb, arsenm, dschuff, mcrosier, sdardis, nemanjai, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, llvm-commits
Differential Revision: https://reviews.llvm.org/D41464
llvm-svn: 321375
Summary:
This makes the TargetMachine interface a bit simpler. We still need
the std::function in TargetIRAnalysis to avoid having to add a
dependency from Analysis to Target.
See discussion:
http://lists.llvm.org/pipermail/llvm-dev/2017-December/119749.html
I avoided adding all of the backend owners to this review since the
change is simple, but let me know if you feel differently about this.
Reviewers: echristo, MatzeB, hfinkel
Reviewed By: hfinkel
Subscribers: jholewinski, jfb, arsenm, dschuff, mcrosier, sdardis, nemanjai, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, llvm-commits
Differential Revision: https://reviews.llvm.org/D41464
llvm-svn: 321234
These optimizations depend on the ExplicitLocals pass to lower TEE
instructions, which is disabled in the ELF ABI, so disable them too.
llvm-svn: 321131
Summary:
- lowers @llvm.global_dtors by adding @llvm.global_ctors
functions which register the destructors with `__cxa_atexit`.
- impements @llvm.global_ctors with wasm start functions and linker metadata
See [here](https://github.com/WebAssembly/tool-conventions/issues/25) for more background.
Subscribers: jfb, dschuff, mgorny, jgravelle-google, aheejin, sunfish
Differential Revision: https://reviews.llvm.org/D41211
llvm-svn: 320774
Headers/Implementation files should be named after the class they
declare/define.
Also eliminated an `#include "llvm/CodeGen/LiveIntervalAnalysis.h"` in
favor of `class LiveIntarvals;`
llvm-svn: 320546
This includes a fix so that it doesn't transform declarations, and it
puts the functionality under control of a command-line option which is off
by default to avoid breaking existing setups.
llvm-svn: 320196
This reverts commit 959e37e669b0c3cfad4cb9f1f7c9261ce9f5e9ae.
That commit doesn't handle the case where main is declared rather than defined,
in particular the even-more special case where main is a prototypeless
declaration (which is of course the one actually used by musl currently).
llvm-svn: 320121
WebAssembly requires caller and callee signatures to match, so the usual
C runtime trick of calling main and having it just work regardless of
whether main is defined as '()' or '(int argc, char *argv[])' doesn't
work. Extend the FixFunctionBitcasts pass to rewrite main to use the
latter form.
llvm-svn: 320041
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.
The MIR printer prints the IR name of a MBB only for block definitions.
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix
Differential Revision: https://reviews.llvm.org/D40422
llvm-svn: 319665
Generalize FixFunctionBitcasts to handle varargs functions. This in
particular fixes the case where clang bitcasts away a varargs when
calling a K&R-style function.
This avoids interacting with tricky ABI details because it operates
at the LLVM IR level before varargs ABI details are exposed.
This fixes PR35385.
llvm-svn: 319186
This adds code to protect WebAssembly's `trunc_s` family of opcodes
from values outside their domain. Even though such conversions have
full undefined behavior in C/C++, LLVM IR's `fptosi` and `fptoui` do
not, and only return undef.
This also implements the proposed non-trapping float-to-int conversion
feature and uses that instead when available.
llvm-svn: 319128
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
llvm-svn: 318490
Previously, an "r" constraint would mean the compiler provides a value
on WebAssembly's operand stack. This was tricky to use properly,
particularly since it isn't possible to declare a new local from within
an inline asm string.
With this patch, "r" provides the value in a WebAssembly local, and the
local index is provided to the inline asm string. This requires inline
asm to use get_local and set_local to read the register. This does
potentially result in larger code size, however inline asm should
hopefully be quite rare in WebAssembly.
This also means that the "m" constraint can no longer be supported, as
WebAssembly has nothing like a "memory operand" that includes an
implicit get_local.
This fixes PR34599 for the wasm32-unknown-unknown-wasm target (though
not for the ELF target).
llvm-svn: 317707
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.
This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.
llvm-svn: 317379
Reverting to investigate layering effects of MCJIT not linking
libCodeGen but using TargetMachine::getNameWithPrefix() breaking the
lldb bots.
This reverts commit r315633.
llvm-svn: 315637
Merge LLVMTargetMachine into TargetMachine.
- There is no in-tree target anymore that just implements TargetMachine
but not LLVMTargetMachine.
- It should still be possible to stub out all the various functions in
case a target does not want to use lib/CodeGen
- This simplifies the code and avoids methods ending up in the wrong
interface.
Differential Revision: https://reviews.llvm.org/D38489
llvm-svn: 315633
Summary:
The pass to fix function bitcasts generates thunks for functions that
are called directly with a mismatching signature. It was also generating
thunks in cases where the function was address-taken, causing aliasing
problems in otherwise valid cases.
This patch tightens the restrictions for when the pass runs.
Reviewers: sunfish, dschuff
Subscribers: jfb, sbc100, llvm-commits, aheejin
Differential Revision: https://reviews.llvm.org/D38640
llvm-svn: 315326
to WasmObjectWriter's constructor.
Fixes the same ownership issue for COFF that r315245 did for MachO:
WasmObjectWriter takes ownership of its MCWasmObjectTargetWriter, so we want to
pass this through to the constructor via a unique_ptr, rather than a raw ptr.
llvm-svn: 315260
Add extending loads and constant offset patterns
A bit more refactoring of the tablegen to make the patterns fairly nice and
uniform between the regular and atomic loads.
Differential Revision: https://reviews.llvm.org/D38523
llvm-svn: 315022
Previously the 'Padding' argument was the number of padding
bytes to add. However most callers that use 'Padding' know
how many overall bytes they need to write. With the previous
code this would mean encoding the LEB once to find out how
many bytes it would occupy and then using this to calulate
the 'Padding' value.
See: https://reviews.llvm.org/D36595
Differential Revision: https://reviews.llvm.org/D37494
llvm-svn: 313393
Not all of these will be able to be used by atomics because tablegen, but it
still seems like a good change by itself.
Differential Revision: https://reviews.llvm.org/D37345
llvm-svn: 312287
Summary: Currently FastISel lowers constexpr calls as indirect calls.
We'd like those to direct calls, and falling back to SelectionDAGISel
handles that.
Reviewers: dschuff, sunfish
Subscribers: jfb, sbc100, llvm-commits, aheejin
Differential Revision: https://reviews.llvm.org/D37073
llvm-svn: 311693
Summary:
Update GCC test suite failure expectations as we add -O0 to the bare tests in
WebAssembly waterfall. There are still several untriaged lld failures.
Reviewers: sbc100, jgravelle-google, dschuff
Reviewed By: dschuff
Subscribers: jfb
Differential Revision: https://reviews.llvm.org/D37100
llvm-svn: 311691
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.
In order to achieve this, the following common code changes were made:
* New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
LSR should do instruction-based addressing evaluations by calling
isLegalAddressingMode() with the Instruction pointers.
* In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
not just loads or stores.
SystemZ changes:
* isLSRCostLess() implemented with Insns first, and without ImmCost.
* New function supportedAddressingMode() that is a helper for TTI methods
looking at Instructions passed via pointers.
Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262https://reviews.llvm.org/D35049
llvm-svn: 308729
Summary: Continuing the work from https://reviews.llvm.org/D33240, this change introduces an element unordered-atomic memset intrinsic. This intrinsic is essentially memset with the implementation requirement that all stores used for the assignment are done with unordered-atomic stores of a given element size.
Reviewers: eli.friedman, reames, mkazantsev, skatkov
Reviewed By: reames
Subscribers: jfb, dschuff, sbc100, jgravelle-google, aheejin, efriedma, llvm-commits
Differential Revision: https://reviews.llvm.org/D34885
llvm-svn: 307854
Summary:
Element atomic intrinsicAtomic instructions are not yet supported in WebAssembly, so we mark them as
unsupported for the moment.
Reviewers: sunfish, dschuff, sbc100
Reviewed By: dschuff, sbc100
Subscribers: jfb, sbc100, jgravelle-google
Differential Revision: https://reviews.llvm.org/D35322
llvm-svn: 307841
Summary:
Revision 307796 caused an internal build break in WebAssembly bots in the form of a
crash. ex:
Here's the crash dump from one of the failing tests:
/usr/local/google/home/blaikie/dev/llvm/build/default/./bin/llc < /usr/local/google/home/blaikie/dev/llvm/src/test/CodeGen/WebAssembly/global.ll -asm-verbose=false -disable-wasm-fallthrough-return-opt -disable-wasm-explicit-locals | /usr/local/google/home/blaikie/dev/llvm/build/default/./bin/FileCheck /usr/local/google/home/blaikie/dev/llvm/src/test/CodeGen/WebAssembly/global.ll
--
Exit Code: 2
Command Output (stderr):
--
Stack dump:
0. Program arguments: build/default/./bin/llc -asm-verbose=false -disable-wasm-fallthrough-return-opt -disable-wasm-explicit-locals
1. Running pass 'Function Pass Manager' on module '<stdin>'.
2. Running pass 'WebAssembly Assembly Printer' on function '@call_memcpy'
FileCheck error: '-' is empty.
FileCheck command line: build/default/./bin/FileCheck src/test/CodeGen/WebAssembly/global.ll
The problem is in lib/Target/WebAssembly/WebAssemblyRuntimeLibcallSignatures.cpp. There’s an array declared:
545 static const char *
Fix to web assembly lib call list
Summary:
Revision 307796 caused an internal build break in WebAssembly bots in the form of a
crash. ex:
Here's the crash dump from one of the failing tests:
/usr/local/google/home/blaikie/dev/llvm/build/default/./bin/llc < /usr/local/google/home/blaikie/dev/llvm/src/test/CodeGen/WebAssembly/global.ll -asm-verbose=false -disable-wasm-fallthrough-return-opt -disable-wasm-explicit-locals | /usr/local/google/home/blaikie/dev/llvm/build/default/./bin/FileCheck /usr/local/google/home/blaikie/dev/llvm/src/test/CodeGen/WebAssembly/global.ll
--
Exit Code: 2
Command Output (stderr):
--
Stack dump:
0. Program arguments: build/default/./bin/llc -asm-verbose=false -disable-wasm-fallthrough-return-opt -disable-wasm-explicit-locals
1. Running pass 'Function Pass Manager' on module '<stdin>'.
2. Running pass 'WebAssembly Assembly Printer' on function '@call_memcpy'
FileCheck error: '-' is empty.
FileCheck command line: build/default/./bin/FileCheck src/test/CodeGen/WebAssembly/global.ll
The problem is in lib/Target/WebAssembly/WebAssemblyRuntimeLibcallSignatures.cpp. There’s an array declared:
static const char *
RuntimeLibcallNames[RTLIB::UNKNOWN_LIBCALL] = {
That is defining a runtime lib call name for each entry in the enum RTLIB:Libcall from include/llvm/CodeGen/RuntimeLibcalls.h.
Revision 307796 added entries to the enum, but didn’t add entries to the RuntimeLibcallNames array, which caused a crash when attempting
to access past the end of the array.
This patch fixes the issue by adding the element atomic memmove to the WebAssembly arrays.
Reviewed by: reames
llvm-svn: 307831
This ensures that symbolic relocations are generated for stack
pointer manipulations.
These relocations are of type R_WEBASSEMBLY_GLOBAL_INDEX_LEB.
This change also adds support for reading relocations of this
type in WasmObjectFile.cpp.
Since its a globally imported symbol this does mean that
the get_global/set_global instruction won't be valid until
the objects are linked that global used in no longer an
imported global.
Differential Revision: https://reviews.llvm.org/D34172
llvm-svn: 305616
These symbols were previously not being marked as functions
so were appearing as globals instead, and with the incorrect
relocation type.
Without this fix, objects that take address of external
functions include them as global imports rather than function
imports which then fails at link time.
Differential Revision: https://reviews.llvm.org/D34068
llvm-svn: 305263
Summary: The method TargetTransformInfo::getRegisterBitWidth() is declared const, but the type erasing implementation classes (TargetTransformInfo::Concept & TargetTransformInfo::Model) that were introduced by Chandler in https://reviews.llvm.org/D7293 do not have the method declared const. This is an NFC to tidy up the const consistency between TTI and its implementation.
Reviewers: chandlerc, rnk, reames
Reviewed By: reames
Subscribers: reames, jfb, arsenm, dschuff, nemanjai, nhaehnle, javed.absar, sbc100, jgravelle-google, llvm-commits
Differential Revision: https://reviews.llvm.org/D33903
llvm-svn: 305189
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
The change cleans up and unifies the handling of relocation
entries in WasmObjectWriter. Type index relocation no longer
need to be handled separately.
The only externally visible change should be that type
index relocations are no longer grouped at the end.
Differential Revision: https://reviews.llvm.org/D33918
llvm-svn: 304816
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
Undefined externals don't need to have a size or an offset.
This was broken by r303915. Added a test for this case.
This fixes the "Compile LLVM Torture (o)" step on the wasm
waterfall.
Differential Revision: https://reviews.llvm.org/D33803
llvm-svn: 304505
TargetPassConfig is not useful for targets that do not use the CodeGen
library, so we may just as well store a pointer to an
LLVMTargetMachine instead of just to a TargetMachine.
While at it, also change the constructor to take a reference instead of a
pointer as the TM must not be nullptr.
llvm-svn: 304247
Summary:
Currently FPOWI defaults to Legal and LegalizeDAG.cpp turns Legal into Expand for this opcode because Legal is a "lie".
This patch changes the default for this opcode to Expand and removes the hack from LegalizeDAG.cpp. It also removes all the code in the targets that set this opcode to Expand themselves since they can just rely on the default.
Reviewers: spatel, RKSimon, efriedma
Reviewed By: RKSimon
Subscribers: jfb, dschuff, sbc100, jgravelle-google, nemanjai, javed.absar, andrew.w.kaylor, llvm-commits
Differential Revision: https://reviews.llvm.org/D33530
llvm-svn: 304215
This provides a new way to access the TargetMachine through
TargetPassConfig, as a dependency.
The patterns replaced here are:
* Passes handling a null TargetMachine call
`getAnalysisIfAvailable<TargetPassConfig>`.
* Passes not handling a null TargetMachine
`addRequired<TargetPassConfig>` and call
`getAnalysis<TargetPassConfig>`.
* MachineFunctionPasses now use MF.getTarget().
* Remove all the TargetMachine constructors.
* Remove INITIALIZE_TM_PASS.
This fixes a crash when running `llc -start-before prologepilog`.
PEI needs StackProtector, which gets constructed without a TargetMachine
by the pass manager. The StackProtector pass doesn't handle the case
where there is no TargetMachine, so it segfaults.
Related to PR30324.
Differential Revision: https://reviews.llvm.org/D33222
llvm-svn: 303360
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.
This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.
The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
affects all targets that use frame pseudo instructions and touched many
files although the changes are uniform.
- Access to frame properties are implemented using special instructions
rather than calls getOperand(N).getImm(). For X86 and ARM such
replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
instruction. These involve proper instruction initialization and
methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
frame parts initialized inside frame instruction pair and outside it.
The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.
Differential Revision: https://reviews.llvm.org/D32394
llvm-svn: 302527
Summary:
Refactoring changed paramHasAttr(1 + i) to paramHasAttr(0), fix that to
paramHasAttr(i).
Add more tests to WebAssemblyOptimizeReturned that catch that
regression.
Reviewers: dschuff
Subscribers: jfb, sbc100, llvm-commits
Differential Revision: https://reviews.llvm.org/D32136
llvm-svn: 300502
This avoids the confusing 'CS.paramHasAttr(ArgNo + 1, Foo)' pattern.
Previously we were testing return value attributes with index 0, so I
introduced hasReturnAttr() for that use case.
llvm-svn: 300367
Add hasParamAttribute() and use it instead of hasAttribute(ArgNo+1,
Kind) everywhere.
The fact that the AttributeList index for an argument is ArgNo+1 should
be a hidden implementation detail.
NFC
llvm-svn: 300272
This seems like a much more natural API, based on Derek Schuff's
comments on r300015. It further hides the implementation detail of
AttributeList that function attributes come last and appear at index
~0U, which is easy for the user to screw up. git diff says it saves code
as well: 97 insertions(+), 137 deletions(-)
This also makes it easier to change the implementation, which I want to
do next.
llvm-svn: 300153
Add support for the new relocations and linking metadata section support in
https://github.com/WebAssembly/tool-conventions/blob/master/Linking.md. In
particular, this allows LLVM to indicate which variable is the stack pointer,
so that it can be linked with other objects.
This also adds support for emitting type relocations for call_indirect
instructions.
Right now, this is mainly tested by using wabt and hexdump to examine the
output on selected testcases. We'll add more tests as the design stablizes
and more of the pieces are in place.
llvm-svn: 299141
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.
Rename AttributeSetImpl to AttributeListImpl to follow suit.
It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.
Reviewers: sanjoy, javed.absar, chandlerc, pete
Reviewed By: pete
Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits
Differential Revision: https://reviews.llvm.org/D31102
llvm-svn: 298393
A recent change switch the in-memory wasm value types
to be signed integers, but I missing a few cases where
these were being writing to the binary.
Differential Revision: https://reviews.llvm.org/D31014
Patch by Sam Clegg
llvm-svn: 297991
Previously we were using the encoded LEB hex values
for the value types. This change uses the decoded
negative value and the LEB encoder to write them out.
Differential Revision: https://reviews.llvm.org/D30847
Patch by Sam Clegg
llvm-svn: 297777
To facilitate this, add a new hidden command-line option to disable
the explicit-locals pass. That causes llc to emit invalid code that doesn't
have all locals converted to get_local/set_local, however it simplifies
testwriting in many cases.
llvm-svn: 296540
With the "wasm32-unknown-unknown-wasm" triple, this allows writing out
simple wasm object files, and is another step in a larger series toward
migrating from ELF to general wasm object support. Note that this code
and the binary format itself is still experimental.
llvm-svn: 296190
LLVM CodeGen emits references to external symbols that are never declared in
LLVM IR level, so they have no declared signature. However, WebAssembly requires
all functions be declared with signatures. This patch adds a table for providing
signatures for known runtime libcalls that will be used in subsequent patches to
emit declarations for such functions.
llvm-svn: 295857
This just adds the basic skeleton for supporting a new object file format.
All of the actual encoding will be implemented in followup patches.
Differential Revision: https://reviews.llvm.org/D26722
llvm-svn: 295803
WebAssembly varargs functions use a significantly different ABI than
non-varargs functions, and the current code in
WebAssemblyFixFunctionBitcasts doesn't handle that difference. For now,
just avoid creating wrapper functions in the presence of varargs.
llvm-svn: 292645
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.
See https://reviews.llvm.org/D28057 for the whole discussion.
Differential Revision: https://reviews.llvm.org/D28556
llvm-svn: 291891
updated instructions:
pmulld, pmullw, pmulhw, mulsd, mulps, mulpd, divss, divps, divsd, divpd, addpd and subpd.
special optimization case which replaces pmulld with pmullw\pmulhw\pshuf seq.
In case if the real operands bitwidth <= 16.
Differential Revision: https://reviews.llvm.org/D28104
llvm-svn: 291657
When we collect 2 uses of a function in FindUses and then RAUW when we
visit the first, we end up visiting the wrapper (because the second was
RAUW'd). We still want to use RAUW instead of just Use->set() because
it has special handling for Constants, so this patch just ensures that
only one use of each constant is added to the work list.
Differential Revision: https://reviews.llvm.org/D28504
llvm-svn: 291603
Gracefully leave code that performs function-pointer bitcasts implying
non-trivial pointer conversions alone, rather than aborting, since it's
just undefined behavior.
llvm-svn: 291326
WebAssembly requires caller and callee signatures to match exactly. In LLVM,
there are a variety of circumstances where signatures may be mismatched in
practice, and one can bitcast a function address to another type to call it
as that type. This patch adds a pass which replaces bitcasted function
addresses with wrappers to replace the bitcasts.
This doesn't catch everything, but it does match many common cases.
llvm-svn: 291315
Instead, expose whether the current type is an array or a struct, if an array
what the upper bound is, and if a struct the struct type itself. This is
in preparation for a later change which will make PointerType derive from
Type rather than SequentialType.
Differential Revision: https://reviews.llvm.org/D26594
llvm-svn: 288458
Support a new assembler directive, .import_global, to declare imported
global variables (i.e. those with external linkage and no
initializer). The linker turns these into wasm imports.
Patch by Jacob Gravelle
Differential Revision: https://reviews.llvm.org/D26875
llvm-svn: 288296
This patch updates a bunch of places where add_dependencies was being explicitly called to add dependencies on intrinsics_gen to instead use the DEPENDS named parameter. This cleanup is needed for a patch I'm working on to add a dependency debugging mode to the build system.
llvm-svn: 287206
Since IMPLIFIT_DEF instructions are omitted in the output, when the output
of an IMPLICIT_DEF instruction is stackified, the resulting register lacks
an explicit push, leading to a push/pop mismatch. Fix this by converting
such IMPLICIT_DEFs into CONST_I32 0 instructions so that they have explicit
pushes.
llvm-svn: 286274
Because we shift the stack pointer by an unknown amount, we need an
additional pointer. In the case where we have variable-size objects
as well, we can't reuse the frame pointer, thus three pointers.
Patch by Jacob Gravelle
Differential Revision: https://reviews.llvm.org/D26263
llvm-svn: 286160
Update the README.txt with newer information, add a link to the Emscripten
page explaining the current easiest way to use the LLVM wasm backend, and
mention that other ways of using the LLVM wasm backend are in development.
llvm-svn: 285215
This changes locals from being declared by the emitLocal hook in
WebAssemblyTargetStreamer, rather than with an instruction. After exploring
the infastructure in LLVM more, this seems to make more sense since
declaring locals doesn't use an encoded opcode.
This also adds more 0xd opcodes, type encodings, and miscellaneous
binary encoding bits.
llvm-svn: 285040
This patch adds a pass, controlled by an option and off by default for
now, for making implicit get_local/set_local explicit. This simplifies
emitting wasm with MC.
Differential Revision: https://reviews.llvm.org/D25836
llvm-svn: 285009
Summary:
Need to reorder the operands to have the callee as the last argument.
Adds a pseudo-instruction, and a pass to lower it into a real
call_indirect.
This is the first of two options for how to fix the problem.
Reviewers: dschuff, sunfish
Subscribers: jfb, beanz, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D25708
llvm-svn: 284840
All of these existed because MSVC 2013 was unable to synthesize default
move ctors. We recently dropped support for it so all that error-prone
boilerplate can go.
No functionality change intended.
llvm-svn: 284721
Per spec changes, this implements block signatures, and adds just enough
logic to produce correct block signatures at the ends of functions.
Differential Revision: https://reviews.llvm.org/D25144
llvm-svn: 283503
Per spec changes, store instructions in WebAssembly no longer have a return
value. Update the instruction descriptions.
Differential Revision: https://reviews.llvm.org/D25122
llvm-svn: 283501
WebAssembly has officially switched from being an AST to being a stack
machine. Update various bits of terminology and README.md entries
accordingly.
llvm-svn: 283154
Register stackification currently checks VNInfo for changes. Make that
more accurate by testing each intervening instruction for any other defs
to the same virtual register.
Patch by Jacob Gravelle
Differential Revision: https://reviews.llvm.org/D24942
llvm-svn: 282886
When we have dynamic allocas we have a frame pointer, and
when we're lowering frame indexes we should make sure we use it.
Patch by Jacob Gravelle
Differential Revision: https://reviews.llvm.org/D24889
llvm-svn: 282442
Summary:
I want to separate out the notions of invariance and dereferenceability
at the MI level, so that they correspond to the equivalent concepts at
the IR level. (Currently an MI load is MI-invariant iff it's
IR-invariant and IR-dereferenceable.)
First step is renaming this function.
Reviewers: chandlerc
Subscribers: MatzeB, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D23370
llvm-svn: 281125
Summary: This patch adds asm.js-style setjmp/longjmp handling support for WebAssembly. It also uses JavaScript's try and catch mechanism.
Reviewers: jpp, dschuff
Subscribers: jfb, dschuff
Differential Revision: https://reviews.llvm.org/D24121
llvm-svn: 280415
Summary: This patch adds asm.js-style setjmp/longjmp handling support for WebAssembly. It also uses JavaScript's try and catch mechanism.
Reviewers: jpp, dschuff
Subscribers: jfb, dschuff
Differential Revision: https://reviews.llvm.org/D23928
llvm-svn: 280302
Summary:
If the register has a negative value then unsigned overflow will occur;
this case is sometimes even created intentionally by LSR. For now
disable GA+reg folding. Fixes PR29127
Differential Revision: https://reviews.llvm.org/D24053
llvm-svn: 280285
Rename AllVRegsAllocated to NoVRegs. This avoids the connotation of
running after register and simply describes that no vregs are used in
a machine function. With that we can simply compute the property and do
not need to dump/parse it in .mir files.
Differential Revision: http://reviews.llvm.org/D23850
llvm-svn: 279698
The names of the tablegen defs now match the names of the ISD nodes.
This makes the world a slightly saner place, as previously "fround" matched
ISD::FP_ROUND and not ISD::FROUND.
Differential Revision: https://reviews.llvm.org/D23597
llvm-svn: 279129
The WebAssemly spec removing the return value from store instructions, so
remove the associated optimization from LLVM.
This patch leaves the store instruction operands in place for now, so stores
now always write to "$drop"; these will be removed in a seperate patch.
llvm-svn: 279100
This patch changes the code structure of
WebAssemblyLowerEmscriptenException pass to support both exception
handling and setjmp/longjmp. It also changes the name of the pass and
the source file.
1. Change the file/pass name to WebAssemblyLowerEmscriptenExceptions ->
WebAssemblyLowerEmscriptenEHSjLj to make it clear that it supports both
EH and SjLj
2. List function / global variable names at the top so they
can be changed easily
3. Some cosmetic changes
Patch by Heejin Ahn
Differential Revision: https://reviews.llvm.org/D23588
llvm-svn: 279075
This reverts commit r278967, since the new test is failing when you
don't build the WebAssembly target (most people, since it's
off-by-default).
llvm-svn: 278973
This patch adds -emscripten-cxx-exceptions-whitelist option to
WebAssemblyLowerEmscriptenExceptions pass. This options is the list of
function names in which Emscripten-style exception handling is enabled.
This is to support emscripten's EXCEPTION_CATCHING_WHITELIST which
exists because of the performance impact of emscripten's non-zero-cost
EH method.
Patch by Heejin Ahn
Differential Revision: https://reviews.llvm.org/D23292
llvm-svn: 278171
* Delete extra '_' prefixes from JS library function names. fixImports()
function in JS glue code deals with this for wasm.
* Change command-line option names in order to be consistent with
asm.js.
* Add missing lowering code for llvm.eh.typeid.for intrinsics
* Delete commas in mangled function names
* Fix a function argument attributes bug. Because we add the pointer to
the original callee as the first argument of invoke wrapper, all
argument attribute indices have to be incremented by one.
Patch by Heejin Ahn
Differential Revision: https://reviews.llvm.org/D23258
llvm-svn: 278081
Previously, FastISel for WebAssembly wasn't checking the return value of
`getRegForValue` in certain cases, which would generate instructions
referencing NoReg. This patch fixes this behavior.
Patch by Dominic Chen
Differential Revision: https://reviews.llvm.org/D23100
llvm-svn: 277742
Summary: This patch implements CFI for WebAssembly. It modifies the
LowerTypeTest pass to pre-assign table indexes to functions that are
called indirectly, and lowers type checks to test against the
appropriate table indexes. It also modifies the WebAssembly backend to
support a special ".indidx" assembly directive that propagates the table
index assignments out to the linker.
Patch by Dominic Chen
Differential Revision: https://reviews.llvm.org/D21768
llvm-svn: 277398
Summary: This patch includes asm.js-style exception handling support for
WebAssembly. The WebAssembly MVP does not have any support for
unwinding or non-local control flow. In order to support C++ exceptions,
emscripten currently uses JavaScript exceptions along with some support
code (written in JavaScript) that is bundled by emscripten with the
generated code.
This scheme lowers exception-related instructions for wasm such that
wasm modules can be compatible with emscripten's existing scheme and
share the support code.
Patch by Heejin Ahn
Differential Revision: https://reviews.llvm.org/D22958
llvm-svn: 277391
Avoid implicit conversions from MachineInstrBundleIterator to
MachineInstr* in the WebAssembly backend by preferring MachineInstr&
over MachineInstr*.
llvm-svn: 274912
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr. This is a
general API improvement.
Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other. Instead I've done everything as a block and just
updated what was necessary.
This is mostly mechanical fixes: adding and removing `*` and `&`
operators. The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency. Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy. I couldn't run tests
for AVR since llc doesn't link with it turned on.
llvm-svn: 274189
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.
llvm-svn: 272512
Under emscripten, C code can take the address of a function implemented
in Javascript (which is exposed via an import in wasm). Because imports
do not have linear memory address in wasm, we need to generate a thunk
to be the target of the indirect call; it call the import directly.
To make this possible, LLVM needs to emit the type signatures for these
functions, because they may not be called directly or referred to other
than where the address is taken.
This uses s new .s directive (.functype) which specifies the signature.
Differential Revision: http://reviews.llvm.org/D20891
Re-apply r271599 but instead of bailing with an error when a declared
function has multiple returns, replace it with a pointer argument. Also
add the test case I forgot to 'git add' last time around.
llvm-svn: 271703
This reverts r271599, it broke the integration tests.
More places than I expected had nontrival return types in imports, or
else the check was wrong.
llvm-svn: 271606
Under emscripten, C code can take the address of a function implemented
in Javascript (which is exposed via an import in wasm). Because imports
do not have linear memory address in wasm, we need to generate a thunk
to be the target of the indirect call; it call the import directly.
To make this possible, LLVM needs to emit the type signatures for these
functions, because they may not be called directly or referred to other
than where the address is taken.
This uses s new .s directive (.functype) which specifies the signature.
Differential Revision: http://reviews.llvm.org/D20891
llvm-svn: 271599
Instead of this:
i32.const $push10=, __stack_pointer
i32.load $push11=, 0($pop10)
Emit this:
i32.const $push10=, 0
i32.load $push11=, __stack_pointer($pop10)
It's not currently clear which is better, though there's a chance the second
form may be better at overall compression. We can revisit this when we have
more data; for now it makes sense to make PEI consistent with isel.
Differential Revision: http://reviews.llvm.org/D20411
llvm-svn: 270635
Use the more specific LiveInterval::removeSegment instead of
LiveInterval::shrinkToUses when we know the specific range that's
being removed.
llvm-svn: 270463
This saves a small amount of code size, and is a first small step toward
passing values on the stack across block boundaries.
Differential Review: http://reviews.llvm.org/D20450
llvm-svn: 270294
Don't expand divisions by constants if it would require multiple instructions.
The current assumption is that engines will perform the desired optimizations.
llvm-svn: 269930
We currently don't represent get_local and set_local explicitly; they
are just implied by virtual register use and def. This avoids a lot of
clutter, but it does complicate stackifying: get_locals read their
operands at their position in the stack evaluation order, rather than
at their parent instruction. This patch adds code to walk the stack to
determine the precise ordering, when needed.
llvm-svn: 269854
PrologEpilogInserter has these 3 phases, which are related, but not
all of them are needed by all targets. This patch reorganizes PEI's
varous functions around those phases for more clear separation. It also
introduces a new TargetMachine hook, usesPhysRegsForPEI, which is true
for non-virtual targets. When it is true, all the phases operate as
before, and PEI requires the AllVRegsAllocated property on
MachineFunctions. Otherwise, CSR spilling and scavenging are skipped and
only prolog/epilog insertion/frame finalization is done.
Differential Revision: http://reviews.llvm.org/D18366
llvm-svn: 269750
MachineInstr::isSafeToMove is more conservative than is needed here;
use a more explicit check, and incorporate knowledge of some
WebAssembly-specific opcodes.
llvm-svn: 269736
compiler-rt/libgcc shift routines expect the shift count to be an i32, so
use i32 as the shift count for shifts that are legalized to libcalls. This
also reverts r268991, now that the signatures are correct.
llvm-svn: 269531
Move the register stackification and coloring passes to run very late, after
PEI, tail duplication, and most other passes. This means that all code emitted
and expanded by those passes is now exposed to these passes. This also
eliminates the need for prologue/epilogue code to be manually stackified,
which significantly simplifies the code.
This does require running LiveIntervals a second time. It's useful to think
of these late passes not as late optimization passes, but as a domain-specific
compression algorithm based on knowledge of liveness information. It's used to
compress the code after all conventional optimizations are complete, which is
why it uses LiveIntervals at a phase when actual optimization passes don't
typically need it.
Differential Revision: http://reviews.llvm.org/D20075
llvm-svn: 269012
Many files include Passes.h but only a fraction needs to know about the
TargetPassConfig class. Move it into an own header. Also rename
Passes.cpp to TargetPassConfig.cpp while we are at it.
llvm-svn: 269011
Currently the signature of the functions
i128(i128, i32) aka void(i32, i64, i64, i32) doesn't match the signature
of the call emitted by the default lowering, void(i32, i64, i64).
llvm-svn: 268991
This is a step towards removing the rampant undefined behaviour in
SelectionDAG, which is a part of llvm.org/PR26808.
We rename SelectionDAGISel::Select to SelectImpl and update targets to
match, and then change Select to return void and consolidate the
sketchy behaviour we're trying to get away from there.
Next, we'll update backends to implement `void Select(...)` instead of
SelectImpl and eventually drop the base Select implementation.
llvm-svn: 268693
Removed some unused headers, replaced some headers with forward class declarations.
Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'
Patch by Eugene Kosov <claprix@yandex.ru>
Differential Revision: http://reviews.llvm.org/D19219
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
This will become necessary in a subsequent change to make this method
merge adjacent stack adjustments, i.e. it might erase the previous
and/or next instruction.
It also greatly simplifies the calls to this function from Prolog-
EpilogInserter. Previously, that had a bunch of logic to resume iteration
after the call; now it just continues with the returned iterator.
Note that this changes the behaviour of PEI a little. Previously,
it attempted to re-visit the new instruction created by
eliminateCallFramePseudoInstr(). That code was added in r36625,
but I can't see any reason for it: the new instructions will obviously
not be pseudo instructions, they will not have FrameIndex operands,
and we have already accounted for the stack adjustment.
Differential Revision: http://reviews.llvm.org/D18627
llvm-svn: 265036
MachineFunctionProperties represents a set of properties that a MachineFunction
can have at particular points in time. Existing examples of this idea are
MachineRegisterInfo::isSSA() and MachineRegisterInfo::tracksLiveness() which
will eventually be switched to use this mechanism.
This change introduces the AllVRegsAllocated property; i.e. the property that
all virtual registers have been allocated and there are no VReg operands
left.
With this mechanism, passes can declare that they require a particular property
to be set, or that they set or clear properties by implementing e.g.
MachineFunctionPass::getRequiredProperties(). The MachineFunctionPass base class
verifies that the requirements are met, and handles the setting and clearing
based on the delcarations. Passes can also directly query and update the current
properties of the MF if they want to have conditional behavior.
This change annotates the target-independent post-regalloc passes; future
changes will also annotate target-specific ones.
Reviewers: qcolombet, hfinkel
Differential Revision: http://reviews.llvm.org/D18421
llvm-svn: 264593
Summary:
MRI::eliminateFrameIndex can emit several instructions to do address
calculations; these can usually be stackified. Because instructions with
FI operands can have subsequent operands which may be expression trees,
find the top of the leftmost tree and insert the code before it, to keep
the LIFO property.
Also use stackified registers when writing back the SP value to memory
in the epilog; it's unnecessary because SP will not be used after the
epilog, and it results in better code.
Differential Revision: http://reviews.llvm.org/D18234
llvm-svn: 263725
It's failing to build on VS2015 with:
C:\b\build\slave\ClangToTWin\build\src\third_party\llvm\lib\Target\WebAssembly\WebAssemblyRegStackify.cpp(520):
error C2668: 'llvm::make_reverse_iterator': ambiguous call to overloaded function
C:\b\build\slave\ClangToTWin\build\src\third_party\llvm\include\llvm/ADT/STLExtras.h(217):
note: could be 'std::reverse_iterator<llvm::MachineBasicBlock::iterator>
llvm::make_reverse_iterator<llvm::MachineInstrBundleIterator<llvm::MachineInstr>>(IteratorTy)'
with
[
IteratorTy=llvm::MachineInstrBundleIterator<llvm::MachineInstr>
]
C:\b\depot_tools\win_toolchain\vs_files\391bbf1220d3edcd3cc3fccdb56224181e3b13a7\win_sdk\bin\..\..\VC\include\xutility(1217):
note: or 'std::reverse_iterator<llvm::MachineBasicBlock::iterator>
std::make_reverse_iterator<llvm::MachineInstrBundleIterator<llvm::MachineInstr>>(_RanIt)' [found using argument-dependent lookup]
with
[
_RanIt=llvm::MachineInstrBundleIterator<llvm::MachineInstr>
]
I don't have VS2015 locally at the moment, but hopefully this will help.
llvm-svn: 263418
This implements a very simple conservative transformation that doesn't
require more than linear code size growth. There's room for much more
optimization in this space.
llvm-svn: 262982
Implements a mostly-conventional redzone for the userspace
stack. Because we have unsigned load/store offsets we continue to use a
local SP subtracted from the incoming SP but do not write it back to
memory.
Differential Revision: http://reviews.llvm.org/D17525
llvm-svn: 261662
Previously the stack pointer was only written back to memory in the
prolog. But this is wrong for dynamic allocas, for which
target-independent codegen handles SP updates after the prolog (and
possibly even in another BB). Instead update the SP global in
ADJCALLSTACKDOWN which is generated after the SP update sequence.
This will have further refinements when we add red zone support.
llvm-svn: 261579
LLVM converts adds into ors when it can prove that the operands don't share
any non-zero bits. Teach address folding to recognize or instructions with
constant operands with this property that can be folded into addresses as
if they were adds.
llvm-svn: 261562
The stack pointer is bumped when there is a frame pointer or when there
are static-size objects, but was only getting written back when there
were static-size objects.
llvm-svn: 261453
While we still do want reducible control flow, the RequiresStructuredCFG
flag imposes more strict structure constraints than WebAssembly wants.
Unsetting this flag enables critical edge splitting and tail merging.
Also, disable TailDuplication explicitly, as it doesn't support virtual
registers, and was previously only disabled by the RequiresStructuredCFG
flag.
llvm-svn: 261190
These passes are optimizations, and should be disabled when not
optimizing.
Also create an MCCodeGenInfo so the opt level is correctly plumbed to
the backend pass manager.
Also remove the command line flag for disabling register coloring;
running llc with -O0 should now be useful for debugging, so it's not
necessary.
Differential Revision: http://reviews.llvm.org/D17327
llvm-svn: 261176
This fixes very slow compilation on
test/CodeGen/Generic/2010-11-04-BigByval.ll . Note that MaxStoresPerMemcpy
and friends are not yet carefully tuned so the cutoff point is currently
somewhat arbitrary. However, it's important that there be a cutoff point
so that we don't emit unbounded quantities of loads and stores.
llvm-svn: 261050
The register stackifier currently checks for intervening stores (and
loads that may alias them) but doesn't account for the fact that the
instruction being moved may affect intervening loads.
Differential Revision: http://reviews.llvm.org/D17298
llvm-svn: 261014
CopyToReg nodes don't support FrameIndex operands. Other targets select
the FI to some LEA-like instruction, but since we don't have that, we
need to insert some kind of instruction that can take an FI operand and
produces a value usable by CopyToReg (i.e. in a vreg). So insert a dummy
copy_local between Op and its FI operand. This results in a redundant
copy which we should optimize away later (maybe in the post-FI-lowering
peephole pass).
Differential Revision: http://reviews.llvm.org/D17213
llvm-svn: 260987
WebAssembly doesn't require full RPO; topological sorting is sufficient and
can preserve more of the MachineBlockPlacement ordering. Unfortunately, this
still depends a lot on heuristics, because while we use the
MachineBlockPlacement ordering as a guide, we can't use it in places where
it isn't topologically ordered. This area will require further attention.
llvm-svn: 260978
This avoids some complications updating LiveIntervals to be aware of the new
register lifetimes, because we can just compute new intervals from scratch
rather than describe how the old ones have been changed.
llvm-svn: 260971
Instead of passing varargs directly on the user stack, allocate a buffer in
the caller's stack frame and pass a pointer to it. This simplifies the C
ABI (e.g. non-C callers of C functions do not need to use C's user stack if
they have their own mechanism) and allows further optimizations in the future
(e.g. fewer functions may need to use the stack).
Differential Revision: http://reviews.llvm.org/D17048
llvm-svn: 260421
Re-commit of r258951 after fixing layering violation.
The BPF and WebAssembly backends had identical code for emitting errors
for unsupported features, and AMDGPU had very similar code. This merges
them all into one DiagnosticInfo subclass, that can be used by any
backend.
There should be minimal functional changes here, but some AMDGPU tests
have been updated for the new format of errors (it used a slightly
different format to BPF and WebAssembly). The AMDGPU error messages will
now benefit from having precise source locations when debug info is
available.
llvm-svn: 259498
Previously the code assumed all uses of FI on loads and stores were as
addresses. This checks whether the use is the address or a value and
handles the latter case as it does for non-memory instructions.
llvm-svn: 259306
The previous code was incorrect (can't getReg a frameindex). We could instead optimize it to reduce tree height, but I'm not sure that's worthwhile yet because we then try to eliminate the frameindex.
This patch also fixes frame index elimination for operations which may load or store: it used to assume the base was operand 2 and immediate offset operand 1. That's not true for stores, where they're 4 and 3.
llvm-svn: 259305
Refine the test for whether an instruction is in an expression tree so that
it detects when one tree ends and another begins, so we can place a block
at that point, rather than continuing to find the first instruction not in
a tree at all.
llvm-svn: 259294
Add support for frame pointer use in prolog/epilog.
Supports dynamic allocas but not yet over-aligned locals.
Target-independend CG generates SP updates, but we still need to write
back the SP value to memory when necessary.
llvm-svn: 259220
Re-commit of r258951 after fixing layering violation.
The related LLVM patch adds a backend diagnostic type for reporting
unsupported features, this adds a printer for them to clang.
In the case where debug location information is not available, I've
changed the printer to report the location as the first line of the
function, rather than the closing brace, as the latter does not give the
user any information. This also affects optimisation remarks.
Differential Revision: http://reviews.llvm.org/D16590
llvm-svn: 259035
This patch revamps the RegStackifier pass with a new tree traversal mechanism,
enabling three major new features:
- Stackification of values with multiple uses, using the result value of set_local
- More aggressive stackification of instructions with side effects
- Reordering operands in commutative instructions to enable more stackification.
llvm-svn: 259009
Summary:
Just does the simple allocation of a stack object and passes
a pointer to the callee.
Differential Revision: http://reviews.llvm.org/D16610
llvm-svn: 258989
The BPF and WebAssembly backends had identical code for emitting errors
for unsupported features, and AMDGPU had very similar code. This merges
them all into one DiagnosticInfo subclass, that can be used by any
backend.
There should be minimal functional changes here, but some AMDGPU tests
have been updated for the new format of errors (it used a slightly
different format to BPF and WebAssembly). The AMDGPU error messages will
now benefit from having precise source locations when debug info is
available.
The implementation of DiagnosticInfoUnsupported::print must be in
lib/Codegen rather than in the existing file in lib/IR/ to avoid
introducing a dependency from IR to CodeGen.
Differential Revision: http://reviews.llvm.org/D16590
llvm-svn: 258951
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html
"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi
Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark
Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D16471
llvm-svn: 258861
r258781 optimized memcpy/memmove/memcpy so the intrinsic call can return its first argument, but missed the frame index case. Teach it to ignore that case so C code doesn't assert out in these cases.
llvm-svn: 258851
These calls return their first argument, but because LLVM uses an intrinsic
with a void return type, they can't use the returned attribute. Generalize
the store results pass to optimize these calls too.
llvm-svn: 258781
Instructions can be DCE'd after the RegStackify pass. If the instruction which
would be the pop for what would be a push is removed, don't use a push.
llvm-svn: 258694
Previously it failed to add NumArgRegs to the offset and so clobbered an
already-used register. Now just start the numbering after the arg regs
and don't duplicate the add. Test coverage for this coming shortly with
the implementation of byval.
llvm-svn: 258597
Teach the register stackifier to rematerialize constants that have multiple
uses instead of leaving them in registers. In the WebAssembly encoding, it's
the same code size to materialize most constants as it is to read a value
from a register.
llvm-svn: 258142
WebAssembly's stack will never be executable by default, so it isn't
necessary to declare .note.GNU-stack sections to request a non-executable
stack.
Differential Revision: http://reviews.llvm.org/D15969
llvm-svn: 257962
A recent change introduced this assertion failure in some corner cases.
Repro:
mkdir /s/wasm/torture-out ; time /s/wasm/waterfall/src/compile_torture_tests.py --c /s/llvm/out/bin/clang --cxx /s/llvm/out/bin/clang++ --testsuite /s/gcc/gcc/testsuite --fails /s/llvm/llvm/lib/Target/WebAssembly/known_gcc_test_failures.txt --out /s/wasm/torture-out
Or look on the wasm integration bot:
https://build.chromium.org/p/client.wasm.llvm/console
llvm-svn: 257733
A request has been made to the official registry, but an official value is
not yet available. This patch uses a temporary value in order to support
development. When an official value is recieved, the value of EM_WEBASSEMBLY
will be updated.
llvm-svn: 257517
Refactor .param, .result, .local, and .endfunc, as directives, using the
proper MCTargetStreamer mechanism, rather than fake instructions.
llvm-svn: 257511
This patch changes the way labels are referenced. Instead of referencing the
basic-block label name (eg. .LBB0_0), instructions now just have an immediate
which indicates the depth in the control-flow stack to find a label to jump to.
This makes them much closer to what we expect to have in the binary encoding,
and avoids the problem of basic-block label names not being explicit in the
binary encoding.
Also, it terminates blocks and loops with end_block and end_loop instructions,
rather than basic-block label names, for similar reasons.
This will also fix problems where two constructs appear to have the same label,
because we no longer explicitly use labels, so consumers that need labels will
presumably create their own labels, and presumably they won't reuse labels
when they do.
This patch does make the code a little more awkward to read; as a partial
mitigation, this patch also introduces comments showing where the labels are,
and comments on each branch showing where it's branching to.
llvm-svn: 257505
Currently WebAssembly has two kinds of relocations; data addresses and
function addresses. This adds ELF relocations for them, as well as an
MC symbol kind to indicate which type of relocation is needed.
llvm-svn: 257416
Always expect tglobaladdr and texternalsym to be wrapped in
WebAssemblywrapper nodes. Also, split out a regPlusGA from regPlusImm so
that it can special-case global addresses, as they can be folded in more
cases.
Unfortunately this doesn't enable any new optimizations yet due to
SelectionDAG limitations. I'll be submitting changes to the SelectionDAG
infrastructure, along with tests, in a separate patch.
llvm-svn: 257394
.zero is confusing when used with two arguments. Documentation:
This directive emits SIZE 0-valued bytes. SIZE must be an absolute
expression. This directive is actually an alias for the '.skip'
directive so in can take an optional second argument of the value to
store in the bytes instead of zero. Using '.zero' in this way would be
confusing however.
Ref: https://sourceware.org/bugzilla/show_bug.cgi?id=18353
Hexagon and Sparc do the same, and it's all the same to WebAssembly so
let's pick the less confusing of the two.
llvm-svn: 257111
Previously we only supported putting the FI into memory operand offset
fields if there was nothing there already. Now combine them.
Differential Revision: http://reviews.llvm.org/D15941
llvm-svn: 257084
The MC assembler doesn't like using the empty string as a private label
prefix because then it treats all labels as private. This commit reverts
back to the default prefix, which is .L, which is common in ELF targets
and consistent with the LLVM name mangler.
llvm-svn: 257083
The first instruction in a block is what the rend() iterator points to, so
if it moves, we need to re-evaluate rend() so that we continue to iterate
through the rest of the instructions.
llvm-svn: 256953
Heejin Ahn