load instruction
The function `Thumb1InstrInfo::loadRegFromStackSlot` accepts only the `tGPR`
register class. The function serves to emit a `tLDRspi` instruction and
certainly any subset of the `tGPR` register class is a valid destination of the
load.
Differential revision: https://reviews.llvm.org/D42535
llvm-svn: 323514
This is the groundwork for Armv8.2-A FP16 code generation .
Clang passes and returns _Float16 values as floats, together with the required
bitconverts and truncs etc. to implement correct AAPCS behaviour, see D42318.
We will implement half-precision argument passing/returning lowering in the ARM
backend soon, but for now this means that this:
_Float16 sub(_Float16 a, _Float16 b) {
return a + b;
}
gets lowered to this:
define float @sub(float %a.coerce, float %b.coerce) {
entry:
%0 = bitcast float %a.coerce to i32
%tmp.0.extract.trunc = trunc i32 %0 to i16
%1 = bitcast i16 %tmp.0.extract.trunc to half
<SNIP>
%add = fadd half %1, %3
<SNIP>
}
When FullFP16 is *not* supported, we don't make f16 a legal type, and we get
legalization for "free", i.e. nothing changes and everything works as before.
And also f16 argument passing/returning is handled.
When FullFP16 is supported, we do make f16 a legal type, and have 2 places that
we need to patch up: f16 argument passing and returning, which involves minor
tweaks to avoid unnecessary code generation for some bitcasts.
As a "demonstrator" that this works for the different FP16, FullFP16, softfp
modes, etc., I've added match rules to the VSUB instruction description showing
that we can codegen this instruction from IR, but more importantly, also to
some conversion instructions. These conversions were causing issue before in
the FP16 and FullFP16 cases.
I've also added match rules to the VLDRH and VSTRH desriptions, so that we can
actually compile the entire half-precision sub code example above. This showed
that these loads and stores had the wrong addressing mode specified: AddrMode5
instead of AddrMode5FP16, which turned out not be implemented at all, so that
has also been added.
This is the minimal patch that shows all the different moving parts. In patch
2/3 I will add some efficient lowering of bitcasts, and in 2/3 I will add the
remaining Armv8.2-A FP16 instruction descriptions.
Thanks to Sam Parker and Oliver Stannard for their help and reviews!
Differential Revision: https://reviews.llvm.org/D38315
llvm-svn: 323512
Summary: For long shifts, the inlined version takes about 20 instructions on Thumb1. To avoid the code bloat, expand to __aeabi_ calls if target is Thumb1.
Reviewers: samparker
Reviewed By: samparker
Subscribers: samparker, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42401
llvm-svn: 323354
This matches what MSVC does for alloca() function calls on ARM.
Even if MSVC doesn't support VLAs at the language level, it does
support the alloca function.
On the clang level, both the _alloca() (when emulating MSVC, which is
what the alloca() function expands to) and __builtin_alloca() builtin
functions, and VLAs, map to the same LLVM IR "alloca" function - so
within LLVM they're not distinguishable from each other.
Differential Revision: https://reviews.llvm.org/D42292
llvm-svn: 323308
Merging such globals loses the dllexport attribute. Add a test
to check that normal globals still are merged.
Differential Revision: https://reviews.llvm.org/D42127
llvm-svn: 323307
https://reviews.llvm.org/D42402
A lot of these copies are useless (copies b/w VRegs having the same
regclass) and should be cleaned up.
llvm-svn: 323291
1. ReachingDefsAnalysis - Allows to identify for each instruction what is the “closest” reaching def of a certain register. Used by BreakFalseDeps (for clearance calculation) and ExecutionDomainFix (for arbitrating conflicting domains).
2. ExecutionDomainFix - Changes the variant of the instructions in order to minimize domain crossings.
3. BreakFalseDeps - Breaks false dependencies.
4. LoopTraversal - Creatws a traversal order of the basic blocks that is optimal for loops (introduced in revision L293571). Both ExecutionDomainFix and ReachingDefsAnalysis use this to determine the order they will traverse the basic blocks.
This also included the following changes to ExcecutionDepsFix original logic:
1. BreakFalseDeps and ReachingDefsAnalysis logic no longer restricted by a register class.
2. ReachingDefsAnalysis tracks liveness of reg units instead of reg indices into a given reg class.
Additional changes in affected files:
1. X86 and ARM targets now inherit from ExecutionDomainFix instead of ExecutionDepsFix. BreakFalseDeps also was added to the passes they activate.
2. Comments and references to ExecutionDepsFix replaced with ExecutionDomainFix and BreakFalseDeps, as appropriate.
Additional refactoring changes will follow.
This commit is (almost) NFC.
The only functional change is that now BreakFalseDeps will break dependency for all register classes.
Since no additional instructions were added to the list of instructions that have false dependencies, there is no actual change yet.
In a future commit several instructions (and tests) will be added.
This is the first of multiple patches that fix bugzilla https://bugs.llvm.org/show_bug.cgi?id=33869
Most of the patches are intended at refactoring the existent code.
Additional relevant reviews:
https://reviews.llvm.org/D40331https://reviews.llvm.org/D40332https://reviews.llvm.org/D40333https://reviews.llvm.org/D40334
Differential Revision: https://reviews.llvm.org/D40330
Change-Id: Icaeb75e014eff96a8f721377783f9a3e6c679275
llvm-svn: 323087
Fix a performance regression caused by r322737.
While trying to make it easier to replace compares with existing adds and
subtracts, I accidentally stopped it from doing so in some cases. This should
fix that. I'm also fixing another potential bug in that commit.
Differential Revision: https://reviews.llvm.org/D42263
llvm-svn: 322972
Previously, these parts weren't ever checked. The label patterns
need to be extended to match successfully on macho.
Differential Revision: https://reviews.llvm.org/D42126
llvm-svn: 322900
r322086 removed the trailing information describing reg classes for each
register.
This patch adds printing reg classes next to every register when
individual operands/instructions/basic blocks are printed. In the case
of dumping MIR or printing a full function, by default don't print it.
Differential Revision: https://reviews.llvm.org/D42239
llvm-svn: 322867
Every known PE COFF target emits /EXPORT: linker flags into a .drective
section. The AsmPrinter should handle this.
While we're at it, use global_values() and emit each export flag with
its own .ascii directive. This should make the .s file output more
readable.
llvm-svn: 322788
The code wasn't zero-extending correctly, so the comparison could
spuriously fail.
Adds some AArch64 tests to cover this case.
Inspired by D41791.
Differential Revision: https://reviews.llvm.org/D41798
llvm-svn: 322767
It appears that we haven't been prioritizing rules that contain nested
instructions properly. InstructionOperandMatcher didn't override
isHigherPriorityThan so it never compared the instructions/operands/predicates
inside nested instructions.
Fixes PR35926. Thanks to Diana Picus for the bug report.
llvm-svn: 322754
This extends my previous patches to also optimize overflow-checked multiplies during SelectionDAG.
Differential revision: https://reviews.llvm.org/D40922
llvm-svn: 322738
The ARM backend contains code that tries to optimize compares by replacing them with an existing instruction that sets the flags the same way. This allows it to replace a "cmp" with a "adds", generalizing the code that replaces "cmp" with "sub". It also heuristically disables sinking of instructions that could potentially be used to replace compares (currently only if they're next to each other).
Differential revision: https://reviews.llvm.org/D38378
llvm-svn: 322737
Mark G_FPEXT and G_FPTRUNC as legal or libcall, depending on hardware
support, but only for conversions between float and double.
Also add the necessary boilerplate so that the LegalizerHelper can
introduce the required libcalls. This also works only for float and
double, but isn't too difficult to extend when the need arises.
llvm-svn: 322651
Change symbol values in the stack_size section from being 8 bytes, to being a target dependent size.
Differential Revision: https://reviews.llvm.org/D42108
llvm-svn: 322619
For hard float with VFP4, it is legal. Otherwise, we use libcalls.
This needs a bit of support in the LegalizerHelper for soft float
because we didn't handle G_FMA libcalls yet. The support is trivial, as
the only difference between G_FMA and other libcalls that we already
handle is that it has 3 input operands rather than just 2.
llvm-svn: 322366
This patch teaches the Arm back-end to generate the SMMULR, SMMLAR and SMMLSR
instructions from equivalent IR patterns.
Differential Revision: https://reviews.llvm.org/D41775
llvm-svn: 322361
The PeepholeOptimizer would fail for vregs without a definition. If this
was caused by an undef operand abort to keep the code simple (so we
don't need to add logic everywhere to replicate the undef flag).
Differential Revision: https://reviews.llvm.org/D40763
llvm-svn: 322319
When replacing a PHI the PeepholeOptimizer currently takes the register
class of the register at the first operand. This however is not correct
if this argument has a subregister index.
As there is currently no API to query the register class resulting from
applying a subregister index to all registers in a class, we can only
abort in these cases and not perform the transformation.
This changes findNextSource() to require the end of all copy chains to
not use a subregister if there is any PHI in the chain. I had to rewrite
the overly complicated inner loop there to have a good place to insert
the new check.
This fixes https://llvm.org/PR33071 (aka rdar://32262041)
Differential Revision: https://reviews.llvm.org/D40758
llvm-svn: 322313
For hard float, it is legal.
For soft float, we need to lower to 0 - x first, and then we can use the
libcall for G_FSUB. This is undoing some of the canonicalization
performed by the IRTranslator (which introduces G_FNEG when it sees a
0 - x). Ideally, that canonicalization would be performed by a
pre-legalizer pass that would allow targets to opt out of this behaviour
rather than dance around it in the legalizer.
llvm-svn: 322168
Planning to add support for named vregs. This puts is in a conundrum since
physregs are named as well. To rectify this we need to use a sigil other than
'%' for physregs in MIR. We've settled on using '$' for physregs but first we
must repurpose it from external symbols using it, which is what this commit is
all about. We think '&' will have familiar semantics for C/C++ users.
llvm-svn: 322146
In -debug output we print "pred:" whenever a MachineOperand is a
predicate operand in the instruction descriptor, and "opt:" whenever a
MachineOperand is an optional def in the instruction descriptor.
Differential Revision: https://reviews.llvm.org/D41870
llvm-svn: 322096
Since register classes and banks are already printed with the register
definition, don't print it at the end of every instruction anymore.
This follows MIR in this regard and is another step to the unification
of the two formats.
llvm-svn: 322086
Summary:
This commit updates the BufferByteStreamer, used by DebugLocStream
to buffer bytes/comments to put in the debug_loc section, to
make sure that the Buffer and Comments vectors are synced.
Previously, when an SLEB128 or ULEB128 was emitted together with
a comment, the vectors could be out-of-sync if the LEB encoding
added several entries to the Buffer vectors, while we only added
a single entry to the Comments vector.
The goal with this is to get the comments in the debug_loc
section in the .s file correctly aligned.
Example (using ARM as target):
Instead of
.byte 144 @ sub-register DW_OP_regx
.byte 128 @ 256
.byte 2 @ DW_OP_piece
.byte 147 @ 8
.byte 8 @ sub-register DW_OP_regx
.byte 144 @ 257
.byte 129 @ DW_OP_piece
.byte 2 @ 8
.byte 147 @
.byte 8 @
we now get
.byte 144 @ sub-register DW_OP_regx
.byte 128 @ 256
.byte 2 @
.byte 147 @ DW_OP_piece
.byte 8 @ 8
.byte 144 @ sub-register DW_OP_regx
.byte 129 @ 257
.byte 2 @
.byte 147 @ DW_OP_piece
.byte 8 @ 8
Reviewers: JDevlieghere, rnk, aprantl
Reviewed By: aprantl
Subscribers: davide, Ka-Ka, uabelho, aemerson, javed.absar, kristof.beyls, llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D41763
llvm-svn: 321907
Select G_PHI to PHI and manually constrain the result register. This is
very similar to how COPY is handled, so extract and reuse some of that
code.
llvm-svn: 321797
We used to handle G_CONSTANT with pointer type by forcing the type of
the result register to s32 and then letting TableGen handle it.
Unfortunately, setting the type only works for generic virtual
registers, that haven't yet been constrained to a register class (e.g.
those used only by a COPY later on). If the result register has already
been constrained as a use of a previously selected instruction, then
setting the type will assert.
It would be nice to be able to teach TableGen to select pointer
constants the same as integer constants, but since it's such an edge
case (at the moment the only pointer constant that we're generally
interested in is 0, and that is mostly used for comparisons and selects,
which are also not supported by TableGen) it's probably not worth the
effort right now. Instead, handle pointer constants with some trivial
handwritten code.
llvm-svn: 321793
Pointer constants are pretty rare, since we usually represent them as
integer constants and then cast to pointer. One notable exception is the
null pointer constant, which is represented directly as a G_CONSTANT 0
with pointer type. Mark it as legal and make sure it is selected like
any other integer constant.
llvm-svn: 321354
If the SRL node is only used by an AND, we may be able to set the
ExtVT to the width of the mask, making the AND redundant. To support
this, another check has been added in isLegalNarrowLoad which queries
whether the load is valid.
Differential Revision: https://reviews.llvm.org/D41350
llvm-svn: 321259
If a block has N predecessors, then the current algorithm will try to
sink common code to this block N times (whenever we visit a
predecessor). Every attempt to sink the common code includes going
through all predecessors, so the complexity of the algorithm becomes
O(N^2).
With this patch we try to sink common code only when we visit the block
itself. With this, the complexity goes down to O(N).
As a side effect, the moment the code is sunk is slightly different than
before (the order of simplifications has been changed), that's why I had
to adjust two tests (note that neither of the tests is supposed to test
SimplifyCFG):
* test/CodeGen/AArch64/arm64-jumptable.ll - changes in this test mimic
the changes that previous implementation of SimplifyCFG would do.
* test/CodeGen/ARM/avoid-cpsr-rmw.ll - in this test I disabled common
code sinking by a command line flag.
llvm-svn: 321236
The AArch64 backend contains code to optimize {s,u}{add,sub}.with.overflow during SelectionDAG. This commit ports that code to the ARM backend.
Differential revision: https://reviews.llvm.org/D35635
llvm-svn: 321224
We get an assertion in RegBankSelect for code along the lines of
my_32_bit_int = my_64_bit_int, which tends to translate into a 64-bit
load, followed by a G_TRUNC, followed by a 32-bit store. This appears in
a couple of places in the test-suite.
At the moment, the legalizer doesn't distinguish between integer and
floating point scalars, so a 64-bit load will be marked as legal for
targets with VFP, and so will the rest of the sequence, leading to a
slightly bizarre G_TRUNC reaching RegBankSelect.
Since the current support for 64-bit integers is rather immature, this
patch works around the issue by explicitly handling this case in
RegBankSelect and InstructionSelect. In the future, we may want to
revisit this decision and make sure 64-bit integer loads are narrowed
before reaching RegBankSelect.
llvm-svn: 321165
Summary:
Implement lower of unsigned saturation on an interval [0, k] where k + 1 is a power of two using USAT instruction in a similar way to how [~k, k] is lowered using SSAT on ARM models that supports it.
Patch by Marten Svanfeldt
Reviewers: t.p.northover, pbarrio, eastig, SjoerdMeijer, javed.absar, fhahn
Reviewed By: fhahn
Subscribers: fhahn, aemerson, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D41348
llvm-svn: 321164
Search from AND nodes to find whether they can be propagated back to
loads, so that the AND and load can be combined into a narrow load.
We search through OR, XOR and other AND nodes and all bar one of the
leaves are required to be loads or constants. The exception node then
needs to be masked off meaning that the 'and' isn't removed, but the
loads(s) are narrowed still.
Differential Revision: https://reviews.llvm.org/D41177
llvm-svn: 320962
Work towards the unification of MIR and debug output by printing
`@foo` instead of `<ga:@foo>`.
Also print target flags in the MIR format since most of them are used on
global address operands.
Only debug syntax is affected.
llvm-svn: 320682
Recommitting rL319773, which was reverted due to a recursive issue
causing timeouts. This happened because I failed to check whether
the discovered loads could be narrowed further. In the case of a tree
with one or more narrow loads, that could not be further narrowed, as
well as a node that would need masking, an AND could be introduced
which could then be visited and recombined again with the same load.
This could again create the masking load, with would be combined
again... We now check that the load can be narrowed so that this
process stops.
Original commit message:
Search from AND nodes to find whether they can be propagated back to
loads, so that the AND and load can be combined into a narrow load.
We search through OR, XOR and other AND nodes and all bar one of the
leaves are required to be loads or constants. The exception node then
needs to be masked off meaning that the 'and' isn't removed, but the
loads(s) are narrowed still.
Differential Revision: https://reviews.llvm.org/D41177
llvm-svn: 320679
Work towards the unification of MIR and debug output by printing
`%const.0 + 8` instead of `<cp#0+8>` and `%const.0 - 8` instead of
`<cp#0-8>`.
Only debug syntax is affected.
Differential Revision: https://reviews.llvm.org/D41116
llvm-svn: 320564
This is due to PR26161 needing to be resolved before we can fix
big endian bugs like PR35359. The work to split aggregates into smaller LLTs
instead of using one large scalar will take some time, so in the mean time
we'll fall back to SDAG.
Some ARM BE tests xfailed for now as a result.
Differential Revision: https://reviews.llvm.org/D40789
llvm-svn: 320388
This is a preparatory step for D34515.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
- fixes PR34564
- fixes PR35103
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 320355
Test (some of) the patterns for selecting PKHBT and PKHTB. The others
are just very similar to the ones we're testing and there would be
little value in covering them as well.
llvm-svn: 320352
Search from AND nodes to find whether they can be propagated back to
loads, so that the AND and load can be combined into a narrow load.
We search through OR, XOR and other AND nodes and all bar one of the
leaves are required to be loads or constants. The exception node then
needs to be masked off meaning that the 'and' isn't removed, but the
loads(s) are narrowed still.
Differential Revision: https://reviews.llvm.org/D39604
llvm-svn: 319773
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
Summary:
The compiler fails with the following error message:
fatal error: error in backend: ran out of registers during
register allocation
Tail call optimization for Armv8-M.base fails to meet all the required
constraints when handling calls to function pointers where the
arguments take up r0-r3. This is because the pointer to the
function to be called can only be stored in r0-r3, but these are
all occupied by arguments. This patch makes sure that tail call
optimization does not try to handle this type of calls.
Reviewers: chill, MatzeB, olista01, rengolin, efriedma
Reviewed By: olista01, efriedma
Subscribers: efriedma, aemerson, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D40706
llvm-svn: 319664
This matches how it is done on X86.
This allows using emulated tls on windows; in MinGW environments,
native tls isn't supported at the moment.
Differential Revision: https://reviews.llvm.org/D40769
llvm-svn: 319643
output
As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.
Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.
Differential Revision: https://reviews.llvm.org/D40421
llvm-svn: 319445
As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).
Basically:
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed
Differential Revision: https://reviews.llvm.org/D40420
llvm-svn: 319427
Partially reverting enabling of post-legalization store merge
(r319036) for just ARM backend as it is causing incorrect code
in some Thumb2 cases.
llvm-svn: 319331
When lowering a G_BRCOND, we generate a TSTri of the condition against
1, which sets the flags, and then a Bcc which branches based on the
value of the flags.
Unfortunately, we were using the wrong condition code to check whether
we need to branch (EQ instead of NE), which caused all our branches to
do the opposite of what they were intended to do. This patch fixes the
issue by using the correct condition code.
llvm-svn: 319313
This will allow compilation of assembly files targeting armv7e-m without having
to specify the Tag_CPU_arch attribute as a workaround.
Differential revision: https://reviews.llvm.org/D40370
Patch by Ian Tessier!
llvm-svn: 319303
Summary:
From the bug report:
> The problem is that it fails when trying to compare -65536 (or 4294901760) to 0xFFFF,0000. This is because the
> constant in the instruction is sign extended to 64 bits (0xFFFF,FFFF,FFFF,0000) and then compared to the non
> extended 64 bit version expected by TableGen.
>
> In contrast, the DAGISelEmitter generates special code for AND immediates (OPC_CheckAndImm), which does not
> sign extend.
This patch doesn't introduce the special case for AND (and OR) immediates since the majority of it is related to handling known bits that have no effect on the result and GlobalISel doesn't detect known-bits at this time. Instead this patch just ensures that the immediate is extended consistently on both sides of the check.
Thanks to Diana Picus for the detailed bug report.
Reviewers: rovka
Reviewed By: rovka
Subscribers: kristof.beyls, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D40532
llvm-svn: 319252
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.
* Only debug printing is affected. It now follows MIR.
Differential Revision: https://reviews.llvm.org/D40417
llvm-svn: 319187
Unoptimized IR can have linear sequences of stores to an array, where the
initial GEP for the first store is formed from the pointer to the array, and the
GEP for each store after the first is formed from the previous GEP with some
offset in an inductive fashion.
The (large) resulting DAG when analyzed by DAGCombine undergoes an excessive
number of combines as each store node is examined every time its' offset node
is combined with any child of the offset. One of the transformations is
findBetterNeighborChains which assists MergeConsecutiveStores. The former
relies on repeated chain walking to do its' work, however MergeConsecutiveStores
is disabled at O0 which makes the transformation redundant.
Any optimization level other than O0 would invoke InstCombine which would
resolve the chain of GEPs into flat base + offset GEP for each store which
does not exhibit the repeated examination of each store to the array.
Disabling this optimization fixes an excessive compile time issue (30~ minutes
for the test case provided) at O0.
Reviewers: niravd, craig.topper, t.p.northover
Differential Revision: https://reviews.llvm.org/D40193
llvm-svn: 319142
Summary:
Now that store-merge is only generates type-safe stores, do a second
pass just before instruction selection to allow lowered intrinsics to
be merged as well.
Reviewers: jyknight, hfinkel, RKSimon, efriedma, rnk, jmolloy
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33675
llvm-svn: 319036
The commit https://reviews.llvm.org/rL318143 computes incorrectly to offset to
restore LR from.
The number of tPOP operands is 2 (condition) + 2 (implicit def and use of SP) +
count of the popped registers. We need to load LR from just past the last
register, hence the correct offset should be either getNumOperands() - 4 and
getNumExplicitOperands() - 2 (multiplied by 4).
Differential revision: https://reviews.llvm.org/D40305
llvm-svn: 319014
TableGen already generates code for selecting a G_FDIV, so we only need
to add a test.
For the legalizer and reg bank select, we do the same thing as for the
other floating point binary operations: either mark as legal if we have
a FP unit or lower to a libcall, and map to the floating point
registers.
llvm-svn: 318915
TableGen already generates code for selecting a G_FMUL, so we only need
to add a test for that part.
For the legalizer and reg bank select, we do the same thing as the other
floating point binary operators: either mark as legal if we have a FP
unit or lower to a libcall, and map to the floating point registers.
llvm-svn: 318910
Add instruction selector test for RSBri, which is derived from
AsI1_rbin_irs, and make sure it doesn't get mistaken for SUBri, which is
derived from the very similar AsI1_bin_irs pattern.
llvm-svn: 318643
Remove some of the instruction selector tests for binary operators (and,
or, xor). These are all derived from the same kind of TableGen pattern,
AsI1_bin_irs, so there's no point in testing all of them.
llvm-svn: 318642
Enabling and using dwarf exceptions seems like an easier path
to take, than to make the COFF/ARM backend output EHABI directives.
Previously, no EH model was enabled at all on this target.
There's no point in setting UseIntegratedAssembler to false since
GNU binutils doesn't support Windows on ARM, and since we don't
need to support external assembler, we don't need to use register
numbers in cfi directives.
Differential Revision: https://reviews.llvm.org/D39532
llvm-svn: 318510
't' constraint normally only accepts f32 operands, but for VCVT the
operands can be i32. LLVM is overly restrictive and rejects asm like:
float foo() {
float result;
__asm__ __volatile__(
"vcvt.f32.s32 %[result], %[arg1]\n"
: [result]"=t"(result)
: [arg1]"t"(0x01020304) );
return result;
}
Relax the value type for 't' constraint to either f32 or i32.
Differential Revision: https://reviews.llvm.org/D40137
llvm-svn: 318472
Change the calculation for the desired ValueType for non-sign
extending loads, as in those cases we don't care about the
higher bits. This creates a smaller ExtVT and allows for such
combinations as:
(srl (zextload i16, [addr]), 8) -> (zextload i8, [addr + 1])
Differential Revision: https://reviews.llvm.org/D40034
llvm-svn: 318390
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
Because the block-splitting code is multi-purpose, we have to meddle with the
branches when using it to fixup a conditional branch destination. We got the
code right, but forgot to update the CFG so the verifier complained when
expensive checks were on.
Probably harmless since constant-islands comes so late, but best to fix it
anyway.
llvm-svn: 318148
Get rid of the handwritten instruction selector code for handling
G_CONSTANT. This code wasn't checking all the preconditions correctly
anyway, so it's better to leave it to TableGen, which can handle at
least some cases correctly (e.g. MOVi, MOVi16, folding into binary
operations). Also add tests to cover those cases.
llvm-svn: 318146
When we emit a tail call for Armv8-M, but then discover that the caller needs to
save/restore `LR`, we convert the tail call to an ordinary one, since restoring
`LR` takes extra instructions, which may negate the benefits of the tail
call. If the callee, however, takes stack arguments, this conversion is
incorrect, since nothing has been done to pass the stack arguments.
Thus the patch reverts https://reviews.llvm.org/rL294000
Also, we improve the instruction sequence for popping `LR` in the case when we
couldn't immediately find a scratch low register, but we can use as a temporary
one of the callee-saved low registers and restore `LR` before popping other
callee-saves.
Differential Revision: https://reviews.llvm.org/D39599
llvm-svn: 318143
Summary:
This fixes PR35221.
Use pseudo-instructions to let MachineCSE hoist global address computation.
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D39871
llvm-svn: 318081
Make one of the legalizer tests a bit more robust by making sure all
values we're interested in are used (either in a store or a return) and
by using loads instead of constants for obtaining values on fewer than
32 bits. This should make the test less fragile to changes in the
legalize combiner, since those loads are legal (as opposed to the
constants, which were being widened and thus produced opportunities for
the legalize combiner).
llvm-svn: 318047
When generating table jump code for switch statements, place the jump
table label as the first operand in the various addition instructions
in order to enable addressing mode selectors to better match index
computation and possibly fold them into the addressing mode of the
table entry load instruction.
Differential revision: https://reviews.llvm.org/D39752
llvm-svn: 318033
This changes the interface of how targets describe how to legalize, see
the below description.
1. Interface for targets to describe how to legalize.
In GlobalISel, the API in the LegalizerInfo class is the main interface
for targets to specify which types are legal for which operations, and
what to do to turn illegal type/operation combinations into legal ones.
For each operation the type sizes that can be legalized without having
to change the size of the type are specified with a call to setAction.
This isn't different to how GlobalISel worked before. For example, for a
target that supports 32 and 64 bit adds natively:
for (auto Ty : {s32, s64})
setAction({G_ADD, 0, s32}, Legal);
or for a target that needs a library call for a 32 bit division:
setAction({G_SDIV, s32}, Libcall);
The main conceptual change to the LegalizerInfo API, is in specifying
how to legalize the type sizes for which a change of size is needed. For
example, in the above example, how to specify how all types from i1 to
i8388607 (apart from s32 and s64 which are legal) need to be legalized
and expressed in terms of operations on the available legal sizes
(again, i32 and i64 in this case). Before, the implementation only
allowed specifying power-of-2-sized types (e.g. setAction({G_ADD, 0,
s128}, NarrowScalar). A worse limitation was that if you'd wanted to
specify how to legalize all the sized types as allowed by the LLVM-IR
LangRef, i1 to i8388607, you'd have to call setAction 8388607-3 times
and probably would need a lot of memory to store all of these
specifications.
Instead, the legalization actions that need to change the size of the
type are specified now using a "SizeChangeStrategy". For example:
setLegalizeScalarToDifferentSizeStrategy(
G_ADD, 0, widenToLargerAndNarrowToLargest);
This example indicates that for type sizes for which there is a larger
size that can be legalized towards, do it by Widening the size.
For example, G_ADD on s17 will be legalized by first doing WidenScalar
to make it s32, after which it's legal.
The "NarrowToLargest" indicates what to do if there is no larger size
that can be legalized towards. E.g. G_ADD on s92 will be legalized by
doing NarrowScalar to s64.
Another example, taken from the ARM backend is:
for (unsigned Op : {G_SDIV, G_UDIV}) {
setLegalizeScalarToDifferentSizeStrategy(Op, 0,
widenToLargerTypesUnsupportedOtherwise);
if (ST.hasDivideInARMMode())
setAction({Op, s32}, Legal);
else
setAction({Op, s32}, Libcall);
}
For this example, G_SDIV on s8, on a target without a divide
instruction, would be legalized by first doing action (WidenScalar,
s32), followed by (Libcall, s32).
The same principle is also followed for when the number of vector lanes
on vector data types need to be changed, e.g.:
setAction({G_ADD, LLT::vector(8, 8)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(16, 8)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(4, 16)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(8, 16)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(2, 32)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(4, 32)}, LegalizerInfo::Legal);
setLegalizeVectorElementToDifferentSizeStrategy(
G_ADD, 0, widenToLargerTypesUnsupportedOtherwise);
As currently implemented here, vector types are legalized by first
making the vector element size legal, followed by then making the number
of lanes legal. The strategy to follow in the first step is set by a
call to setLegalizeVectorElementToDifferentSizeStrategy, see example
above. The strategy followed in the second step
"moreToWiderTypesAndLessToWidest" (see code for its definition),
indicating that vectors are widened to more elements so they map to
natively supported vector widths, or when there isn't a legal wider
vector, split the vector to map it to the widest vector supported.
Therefore, for the above specification, some example legalizations are:
* getAction({G_ADD, LLT::vector(3, 3)})
returns {WidenScalar, LLT::vector(3, 8)}
* getAction({G_ADD, LLT::vector(3, 8)})
then returns {MoreElements, LLT::vector(8, 8)}
* getAction({G_ADD, LLT::vector(20, 8)})
returns {FewerElements, LLT::vector(16, 8)}
2. Key implementation aspects.
How to legalize a specific (operation, type index, size) tuple is
represented by mapping intervals of integers representing a range of
size types to an action to take, e.g.:
setScalarAction({G_ADD, LLT:scalar(1)},
{{1, WidenScalar}, // bit sizes [ 1, 31[
{32, Legal}, // bit sizes [32, 33[
{33, WidenScalar}, // bit sizes [33, 64[
{64, Legal}, // bit sizes [64, 65[
{65, NarrowScalar} // bit sizes [65, +inf[
});
Please note that most of the code to do the actual lowering of
non-power-of-2 sized types is currently missing, this is just trying to
make it possible for targets to specify what is legal, and how non-legal
types should be legalized. Probably quite a bit of further work is
needed in the actual legalizing and the other passes in GlobalISel to
support non-power-of-2 sized types.
I hope the documentation in LegalizerInfo.h and the examples provided in the
various {Target}LegalizerInfo.cpp and LegalizerInfoTest.cpp explains well
enough how this is meant to be used.
This drops the need for LLT::{half,double}...Size().
Differential Revision: https://reviews.llvm.org/D30529
llvm-svn: 317560
The GlobalISel TableGen backend didn't check for predicates on the
source children. This caused it to generate code for ARM patterns such
as SMLABB or similar, but without properly checking for the sext_16_node
part of the operands. This in turn meant that we would select SMLABB
instead of MLA for simple sequences such as s32 + s32 * s32, which is
wrong (we want a MLA on the full operands, not just their bottom 16
bits).
This patch forces TableGen to skip patterns with predicates on the src
children, so it doesn't generate code for SMLABB and other similar ARM
instructions at all anymore. AArch64 and X86 are not affected.
Differential Revision: https://reviews.llvm.org/D39554
llvm-svn: 317313
The generic dag combiner will fold:
(shl (add x, c1), c2) -> (add (shl x, c2), c1 << c2)
(shl (or x, c1), c2) -> (or (shl x, c2), c1 << c2)
This can create constants which are too large to use as an immediate.
Many ALU operations are also able of performing the shl, so we can
unfold the transformation to prevent a mov imm instruction from being
generated.
Other patterns, such as b + ((a << 1) | 510), can also be simplified
in the same manner.
Differential Revision: https://reviews.llvm.org/D38084
llvm-svn: 317197
Remove the G_FADD testcases from arm-legalizer.mir, they are covered by
arm-legalizer-fp.mir (I probably forgot to delete them when I created
that test).
llvm-svn: 316573
We were generating BLX for all the calls, which was incorrect in most
cases. Update ARMCallLowering to generate BL for direct calls, and BLX,
BX_CALL or BMOVPCRX_CALL for indirect calls.
llvm-svn: 316570
Separate the test cases that deal with calls from the rest of the IR
Translator tests.
We split into 2 different files, one for testing parameter and result
lowering, and one for testing the various different kinds of calls that
can occur (BL, BLX, BX_CALL etc).
llvm-svn: 316569
Swap the compare operands if the lhs is a shift and the rhs isn't,
as in arm and T2 the shift can be performed by the compare for its
second operand.
Differential Revision: https://reviews.llvm.org/D39004
llvm-svn: 316562
This updates the MIRPrinter to include the regclass when printing
virtual register defs, which is already valid syntax for the
parser. That is, given 64 bit %0 and %1 in a "gpr" regbank,
%1(s64) = COPY %0(s64)
would now be written as
%1:gpr(s64) = COPY %0(s64)
While this change alone introduces a bit of redundancy with the
registers block, it allows us to update the tests to be more concise
and understandable and brings us closer to being able to remove the
registers block completely.
Note: We generally only print the class in defs, but there is one
exception. If there are uses without any defs whatsoever, we'll print
the class on all uses. I'm not completely convinced this comes up in
meaningful machine IR, but for now the MIRParser and MachineVerifier
both accept that kind of stuff, so we don't want to have a situation
where we can print something we can't parse.
llvm-svn: 316479
This is in preparation for a verifier check that makes sure
copies are of the same size (when generic virtual registers are involved).
llvm-svn: 316388
This patch implements dynamic stack (re-)alignment for 16-bit Thumb. When
targeting processors, which support only the 16-bit Thumb instruction set
the compiler ignores the alignment attributes of automatic variables and may
silently generate incorrect code.
Differential revision: https://reviews.llvm.org/D38143
llvm-svn: 316289
This converts a large and somewhat arbitrary set of tests to use
update_mir_test_checks. I ran the script on all of the tests I expect
to need to modify for an upcoming mir syntax change and kept the ones
that obviously didn't change the tests in ways that might make it
harder to understand.
llvm-svn: 316137
We end up creating COPY's that are either truncating/extending and this
should be illegal.
https://reviews.llvm.org/D37640
Patch for X86 and ARM by igorb, rovka
llvm-svn: 315240
Unfortunately TableGen doesn't handle this yet:
Unable to deduce gMIR opcode to handle Src (which is a leaf).
Just add some temporary hand-written code to generate the proper MOVsr.
llvm-svn: 315071
Issues addressed since original review:
- Avoid bug in regalloc greedy/machine verifier when forwarding to use
in an instruction that re-defines the same virtual register.
- Fixed bug when forwarding to use in EarlyClobber instruction slot.
- Fixed incorrect forwarding to register definitions that showed up in
explicit_uses() iterator (e.g. in INLINEASM).
- Moved removal of dead instructions found by
LiveIntervals::shrinkToUses() outside of loop iterating over
instructions to avoid instructions being deleted while pointed to by
iterator.
- Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
- The pass no longer forwards COPYs to physical register uses, since
doing so can break code that implicitly relies on the physical
register number of the use.
- The pass no longer forwards COPYs to undef uses, since doing so
can break the machine verifier by creating LiveRanges that don't
end on a use (since the undef operand is not considered a use).
[MachineCopyPropagation] Extend pass to do COPY source forwarding
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
llvm-svn: 314729
LR is an untypical callee saved register in that it is restored into a
different register (PC) and thus does not live-out of the return block.
This case requires the `Restored` flag in CalleeSavedInfo to be cleared.
This fixes a number of cases where this wasn't handled correctly yet.
llvm-svn: 314471
In setupEntryBlockAndCallSites in CodeGen/SjLjEHPrepare.cpp,
we fetch and store the actual frame pointer, but on return via
the longjmp intrinsic, it always was restored into the r7 variable.
On windows, the frame pointer should be restored into r11 instead of r7.
On Darwin (where sjlj exception handling is used by default), the frame
pointer is always r7, both in arm and thumb mode, and likewise, on
windows, the frame pointer always is r11.
On linux however, if sjlj exception handling is enabled (which it isn't
by default), libcxxabi and the user code can be built in differing modes
using different registers as frame pointer. Therefore, when restoring
registers on a platform where we don't always use the same register
depending on code mode, restore both r7 and r11.
Differential Revision: https://reviews.llvm.org/D38253
llvm-svn: 314451
Without this, we could end up trying to get the Nth (0-indexed) element
from a subvector of size N.
Differential Revision: https://reviews.llvm.org/D37880
llvm-svn: 314380
It leads to some improvements, but also a regression for the simple
case, so it's not clearly a good idea.
test/CodeGen/ARM/vcvt.ll now has test coverage to show the difference.
Ultimately, the right solution is probably to custom-lower fp-to-int
conversions, to something like ARMISD::VCVT_F32_S32 plus a bitcast.
It's hard to do the right thing when the implicit bitcast isn't visible
to DAG transforms.
llvm-svn: 314169
This teach simplifyDemandedBits to handle constant splat vector shifts.
This required changing some uses of getZExtValue to getLimitedValue since we can't rely on legalization using getShiftAmountTy for the shift amount.
I believe there may have been a bug in the ((X << C1) >>u ShAmt) handling where we didn't check if the inner shift was too large. I've fixed that here.
I had to add new patterns to ARM because the zext/sext the patterns were trying to look for got turned into an any_extend with this patch. Happy to split that out too, but not sure how to test without this change.
Differential Revision: https://reviews.llvm.org/D37665
llvm-svn: 314139
For the following function:
double fn1(double d0, double d1, double d2) {
double a = -d0 - d1 * d2;
return a;
}
on ARM, LLVM generates code along the lines of
vneg.f64 d0, d0
vmls.f64 d0, d1, d2
i.e., a negate and a multiply-subtract.
The attached patch adds instruction selection patterns to allow it to generate the single instruction
vnmla.f64 d0, d1, d2
(multiply-add with negation) instead, like GCC does.
Committed on behalf of @gergo- (Gergö Barany)
Differential Revision: https://reviews.llvm.org/D35911
llvm-svn: 313972
This is a preparatory step for D34515.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
- fixes PR34564
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 313618
This was causing PR34045 to fire again.
> This is a preparatory step for D34515 and also is being recommitted as its
> first version caused PR34045.
>
> This change:
> - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
> - lowering is done by first converting the boolean value into the carry flag
> using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
> using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
> operations does the actual addition.
> - for subtraction, given that ISD::SUBCARRY second result is actually a
> borrow, we need to invert the value of the second operand and result before
> and after using ARMISD::SUBE. We need to invert the carry result of
> ARMISD::SUBE to preserve the semantics.
> - given that the generic combiner may lower ISD::ADDCARRY and
> ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
> as well otherwise i64 operations now would require branches. This implies
> updating the corresponding test for unsigned.
> - add new combiner to remove the redundant conversions from/to carry flags
> to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
> - fixes PR34045
>
> Differential Revision: https://reviews.llvm.org/D35192
Also revert follow-up r313010:
> [ARM] Fix typo when creating ISD::SUB nodes
>
> In D35192, I accidentally introduced a typo when creating ISD::SUB nodes,
> giving them two values instead of one.
>
> This fails when the merge_values combiner finds one of these nodes.
>
> This change fixes PR34564.
>
> Differential Revision: https://reviews.llvm.org/D37690
llvm-svn: 313044
This is a preparatory step for D34515 and also is being recommitted as its
first version caused PR34045.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 313009
It caused PR34564.
> This is a preparatory step for D34515 and also is being recommitted as its
> first version caused PR34045.
>
> This change:
> - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
> - lowering is done by first converting the boolean value into the carry flag
> using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
> using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
> operations does the actual addition.
> - for subtraction, given that ISD::SUBCARRY second result is actually a
> borrow, we need to invert the value of the second operand and result before
> and after using ARMISD::SUBE. We need to invert the carry result of
> ARMISD::SUBE to preserve the semantics.
> - given that the generic combiner may lower ISD::ADDCARRY and
> ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
> as well otherwise i64 operations now would require branches. This implies
> updating the corresponding test for unsigned.
> - add new combiner to remove the redundant conversions from/to carry flags
> to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
> - fixes PR34045
>
> Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 312980
As discussed on llvm-dev in
http://lists.llvm.org/pipermail/llvm-dev/2017-September/117301.html
this changes the command line interface of llvm-dwarfdump to match the
one used by the dwarfdump utility shipping on macOS. In addition to
being shorter to type this format also has the advantage of allowing
more than one section to be specified at the same time.
In a nutshell, with this change
$ llvm-dwarfdump --debug-dump=info
$ llvm-dwarfdump --debug-dump=apple-objc
becomes
$ dwarfdump --debug-info --apple-objc
Differential Revision: https://reviews.llvm.org/D37714
llvm-svn: 312970
This is a preparatory step for D34515 and also is being recommitted as its
first version caused PR34045.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 312898
rL312641 Allowed llvm.memcpy/memset/memmove to be tail calls when parent
function return the intrinsics's first argument. However on arm-none-eabi
platform, llvm.memcpy will be expanded to __aeabi_memcpy which doesn't
have return value. The fix is to check the libcall name after expansion
to match "memcpy/memset/memmove" before allowing those intrinsic to be
tail calls.
llvm-svn: 312799
These don't add any value as they're just compositions of existing
patterns. However, they can confuse the cost logic in ISel, leading to
duplicated vcvt instructions like in PR33199.
llvm-svn: 312724
Globals that are promoted to an ARM constant pool may alias with another
existing constant pool entry. We need to keep a reference to all globals
that were promoted to each constant pool value so that we can emit a
distinct label for each promoted global. These labels are necessary so
that debug info can refer to the promoted global without an undefined
reference during linking.
Patch by Stephen Crane!
llvm-svn: 312692
Missing these could potentially screw up post-ra scheduling.
Issue found by inspection, so I don't have a real testcase. Included
test just verifies the expected operands after expansion.
Differential Revision: https://reviews.llvm.org/D35156
llvm-svn: 312589
In RWPI code, globals that are not read-only are accessed relative to
the SB register (R9). This is achieved by explicitly generating an ADD
instruction between SB and an offset that we either load from a constant
pool or movw + movt into a register.
llvm-svn: 312521
Summary:
This is a re-roll of D36615 which uses PLT relocations in the back-end
to the call to __xray_CustomEvent() when building in -fPIC and
-fxray-instrument mode.
Reviewers: pcc, djasper, bkramer
Subscribers: sdardis, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D37373
llvm-svn: 312466
A register in CodeGen can be marked as reserved: In that case we
consider the register always live and do not use (or rather ignore)
kill/dead/undef operand flags.
LiveIntervalAnalysis however tracks liveness per register unit (not per
register). We already needed adjustments for this in r292871 to deal
with super/sub registers. However I did not look at aliased register
there. Looking at ARM:
FPSCR (regunits FPSCR, FPSCR~FPSCR_NZCV) aliases with FPSCR_NZCV
(regunits FPSCR_NZCV, FPSCR~FPSCR_NZCV) hence they share a register unit
(FPSCR~FPSCR_NZCV) that represents the aliased parts of the registers.
This shared register unit was previously considered non-reserved,
however given that we uses of the reserved FPSCR potentially violate
some rules (like uses without defs) we should make FPSCR~FPSCR_NZCV
reserved too and stop tracking liveness for it.
This patch:
- Defines a register unit as reserved when: At least for one root
register, the root register and all its super registers are reserved.
- Adjust LiveIntervals::computeRegUnitRange() for new reserved
definition.
- Add MachineRegisterInfo::isReservedRegUnit() to have a canonical way
of testing.
- Stop computing LiveRanges for reserved register units in HMEditor even
with UpdateFlags enabled.
- Skip verification of uses of reserved reg units in the machine
verifier (this usually didn't happen because there would be no cached
liverange but there is no guarantee for that and I would run into this
case before the HMEditor tweak, so may as well fix the verifier too).
Note that this should only affect ARMs FPSCR/FPSCR_NZCV registers today;
aliased registers are rarely used, the only other cases are hexagons
P0-P3/P3_0 and C8/USR pairs which are not mixing reserved/non-reserved
registers in an alias.
Differential Revision: https://reviews.llvm.org/D37356
llvm-svn: 312348
Summary:
LoopVectorizer is creating casts between vec<ptr> and vec<float> types
on ARM when compiling OpenCV. Since, tIs is illegal to directly cast a
floating point type to a pointer type even if the types have same size
causing a crash. Fix the crash using a two-step casting by bitcasting
to integer and integer to pointer/float.
Fixes PR33804.
Reviewers: mkuper, Ayal, dlj, rengolin, srhines
Reviewed By: rengolin
Subscribers: aemerson, kristof.beyls, mkazantsev, Meinersbur, rengolin, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35498
llvm-svn: 312331
Issues addressed since original review:
- Moved removal of dead instructions found by
LiveIntervals::shrinkToUses() outside of loop iterating over
instructions to avoid instructions being deleted while pointed to by
iterator.
- Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
- The pass no longer forwards COPYs to physical register uses, since
doing so can break code that implicitly relies on the physical
register number of the use.
- The pass no longer forwards COPYs to undef uses, since doing so
can break the machine verifier by creating LiveRanges that don't
end on a use (since the undef operand is not considered a use).
[MachineCopyPropagation] Extend pass to do COPY source forwarding
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
llvm-svn: 312328
In the ROPI relocation model, read-only variables are accessed relative
to the PC. We use the (MOV|LDRLIT)_ga_pcrel pseudoinstructions for this.
llvm-svn: 312323
Test constants as well in the PIC tests. These are also represented as
G_GLOBAL_VALUE, and although they are treated just like other globals
for PIC, they won't be for ROPI, so it's good to have this coverage.
llvm-svn: 312319
It caused PR34387: Assertion failed: (RegNo < NumRegs && "Attempting to access record for invalid register number!")
> Issues identified by buildbots addressed since original review:
> - Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
> - The pass no longer forwards COPYs to physical register uses, since
> doing so can break code that implicitly relies on the physical
> register number of the use.
> - The pass no longer forwards COPYs to undef uses, since doing so
> can break the machine verifier by creating LiveRanges that don't
> end on a use (since the undef operand is not considered a use).
>
> [MachineCopyPropagation] Extend pass to do COPY source forwarding
>
> This change extends MachineCopyPropagation to do COPY source forwarding.
>
> This change also extends the MachineCopyPropagation pass to be able to
> be run during register allocation, after physical registers have been
> assigned, but before the virtual registers have been re-written, which
> allows it to remove virtual register COPY LiveIntervals that become dead
> through the forwarding of all of their uses.
llvm-svn: 312178
Summary:
Remove a check for `ARMSubtarget::isTargetDarwin` when determining
whether to use Swift error registers, so that Swift errors work
properly on non-Darwin ARM32 targets (specifically Android).
Before this patch, generated code would save and restores ARM register r8 at
the entry and returns of a function that throws. As r8 is used as a virtual
return value for the object being thrown, this gets overwritten by the restore,
and calling code is unable to catch the error. In turn this caused Swift code
that used `do`/`try`/`catch` to work improperly on Android ARM32 targets.
Addresses Swift bug report https://bugs.swift.org/browse/SR-5438.
Patch by John Holdsworth.
Reviewers: manmanren, rjmccall, aschwaighofer
Reviewed By: aschwaighofer
Subscribers: srhines, aschwaighofer, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D35835
llvm-svn: 312164
Added a combiner which can clean up truncs/extends that are created in
order to make the types work during legalization.
Also moved the combineMerges to the LegalizeCombiner.
https://reviews.llvm.org/D36880
llvm-svn: 312158
Issues identified by buildbots addressed since original review:
- Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
- The pass no longer forwards COPYs to physical register uses, since
doing so can break code that implicitly relies on the physical
register number of the use.
- The pass no longer forwards COPYs to undef uses, since doing so
can break the machine verifier by creating LiveRanges that don't
end on a use (since the undef operand is not considered a use).
[MachineCopyPropagation] Extend pass to do COPY source forwarding
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
llvm-svn: 312154
This change simplifies code that has to deal with
DIGlobalVariableExpression and mirrors how we treat DIExpressions in
debug info intrinsics. Before this change there were two ways of
representing empty expressions on globals, a nullptr and an empty
!DIExpression().
If someone needs to upgrade out-of-tree testcases:
perl -pi -e 's/(!DIGlobalVariableExpression\(var: ![0-9]*)\)/\1, expr: !DIExpression())/g' <MYTEST.ll>
will catch 95%.
llvm-svn: 312144
Summary:
Reverts r311008 to reinstate r310825 with a fix.
Refine alias checking for pseudo vs value to be conservative.
This fixes the original failure in builtbot unittest SingleSource/UnitTests/2003-07-09-SignedArgs.
Reviewers: hfinkel, nemanjai, efriedma
Reviewed By: efriedma
Subscribers: bjope, mcrosier, nhaehnle, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D36900
llvm-svn: 312126
Summary:
Based on Fred's patch here: https://reviews.llvm.org/D6771
I can't seem to commandeer the old review, so I'm creating a new one.
With that change the locations exrpessions are pretty printed inline in the
DIE tree. The output looks like this for debug_loc entries:
DW_AT_location [DW_FORM_data4] (0x00000000
0x0000000000000001 - 0x000000000000000b: DW_OP_consts +3
0x000000000000000b - 0x0000000000000012: DW_OP_consts +7
0x0000000000000012 - 0x000000000000001b: DW_OP_reg0 RAX, DW_OP_piece 0x4
0x000000000000001b - 0x0000000000000024: DW_OP_breg5 RDI+0)
And like this for debug_loc.dwo entries:
DW_AT_location [DW_FORM_sec_offset] (0x00000000
Addr idx 2 (w/ length 190): DW_OP_consts +0, DW_OP_stack_value
Addr idx 3 (w/ length 23): DW_OP_reg0 RAX, DW_OP_piece 0x4)
Simple locations without ranges are printed inline:
DW_AT_location [DW_FORM_block1] (DW_OP_reg4 RSI, DW_OP_piece 0x4, DW_OP_bit_piece 0x20 0x0)
The debug_loc(.dwo) dumping in changed accordingly to factor the code.
Reviewers: dblaikie, aprantl, friss
Subscribers: mgorny, javed.absar, hiraditya, llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D37123
llvm-svn: 312042
Support the selection of G_GLOBAL_VALUE in the PIC relocation model. For
simplicity we use the same pseudoinstructions for both Darwin and ELF:
(MOV|LDRLIT)_ga_pcrel(_ldr).
This is new for ELF, so it requires a small update to the ARM pseudo
expansion pass to make sure it adds the correct constant pool modifier
and add-current-address in the case of ELF.
Differential Revision: https://reviews.llvm.org/D36507
llvm-svn: 311992
ARMv4 doesn't support the "BX" instruction, which has been introduced
with ARMv4t. Adjust the call lowering and tail call implementation
accordingly.
Further changes are necessary to ensure that presence of the v4t feature
is correctly set. Most importantly, the "generic" CPU for thumb-*
triples should include ARMv4t, since thumb mode without thumb support
would naturally be pointless.
Add a couple of asserts to ensure thumb instructions are not emitted
without CPU support.
Differential Revision: https://reviews.llvm.org/D37030
llvm-svn: 311921
Summary:
ARMLoadStoreOpt::FixInvalidRegPairOp() was only checking if one of the
load destination registers to be split overlapped with the base register
if the base register was marked as killed. Since kill flags may not
always be present, this can lead to incorrect code.
This bug was exposed by my MachineCopyPropagation change D30751 breaking
the sanitizer-x86_64-linux-android buildbot.
Also clean up some dead code and add an assert that a register offset is
never encountered by this code, since it does not handle them correctly.
Reviewers: MatzeB, qcolombet, t.p.northover
Subscribers: aemerson, javed.absar, kristof.beyls, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D37164
llvm-svn: 311907
Currently this test causes test failures on some machines, due to isel not being registered. Update the test to run all passes and check emitted assembly instructions for now.
llvm-svn: 311545
Summary: In some cases, shufflevector instruction can be transformed involving insert_subvector instructions. The ARM backend was missing some insert_subvector patterns, causing a failure during instruction selection. AArch64 has similar patterns.
Reviewers: t.p.northover, olista01, javed.absar, rengolin
Reviewed By: javed.absar
Subscribers: aemerson, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D36796
llvm-svn: 311543
Summary:
This change achieves two things:
- Redefine the Custom Event handling instrumentation points emitted by
the compiler to not require dynamic relocation of references to the
__xray_CustomEvent trampoline.
- Remove the synthetic reference we emit at the end of a function that
we used to keep auxiliary sections alive in favour of SHF_LINK_ORDER
associated with the section where the function is defined.
To achieve the custom event handling change, we've had to introduce the
concept of sled versioning -- this will need to be supported by the
runtime to allow us to understand how to turn on/off the new version of
the custom event handling sleds. That change has to land first before we
change the way we write the sleds.
To remove the synthetic reference, we rely on a relatively new linker
feature that preserves the sections that are associated with each other.
This allows us to limit the effects on the .text section of ELF
binaries.
Because we're still using absolute references that are resolved at
runtime for the instrumentation map (and function index) maps, we mark
these sections write-able. In the future we can re-define the entries in
the map to use relative relocations instead that can be statically
determined by the linker. That change will be a bit more invasive so we
defer this for later.
Depends on D36816.
Reviewers: dblaikie, echristo, pcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36615
llvm-svn: 311525
This also changes the TailDuplicator to be configured explicitely
pre/post regalloc rather than relying on the isSSA() flag. This was
necessary to have `llc -run-pass` work reliably.
llvm-svn: 311520
When expanding a BRCOND into a BR_CC, do not create an AND 1
if one already exists.
Review: D36705
Patch by Joel Galenson <jgalenson@google.com>
llvm-svn: 311447
The ARM backend should call setBooleanContents so that it can
use known bits to make some optimizations.
Review: D35821
Patch by Joel Galenson <jgalenson@google.com>
llvm-svn: 311446
This is the exact same fix as in SVN r247254. In that commit, the fix was
applied only for isVTRNMask and isVTRN_v_undef_Mask, but the same issue
is present for VZIP/VUZP as well.
This fixes PR33921.
Differential Revision: https://reviews.llvm.org/D36899
llvm-svn: 311258
Two issues identified by buildbots were addressed:
- The pass no longer forwards COPYs to physical register uses, since
doing so can break code that implicitly relies on the physical
register number of the use.
- The pass no longer forwards COPYs to undef uses, since doing so
can break the machine verifier by creating LiveRanges that don't
end on a use (since the undef operand is not considered a use).
[MachineCopyPropagation] Extend pass to do COPY source forwarding
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
Reviewers: qcolombet, javed.absar, MatzeB, jonpa
Subscribers: jyknight, nemanjai, llvm-commits, nhaehnle, mcrosier, mgorny
Differential Revision: https://reviews.llvm.org/D30751
llvm-svn: 311135
This reverts commit r311038.
Several buildbots are breaking, and at least one appears to be due to
the forwarding of physical regs enabled by this change. Reverting while
I investigate further.
llvm-svn: 311062
When lowering a VLA, we emit a __chstk call. However, this call can
internally clobber CPSR. We did not mark this register as an ImpDef,
which could potentially allow a comparison to be hoisted above the call
to `__chkstk`. In such a case, the CPSR could be clobbered, and the
check invalidated. When the support was initially added, it seemed that
the call would take care of preventing CPSR from being clobbered, but
this is not the case. Mark the register as clobbered to fix a possible
state corruption.
llvm-svn: 311061
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
Reviewers: qcolombet, javed.absar, MatzeB, jonpa
Subscribers: jyknight, nemanjai, llvm-commits, nhaehnle, mcrosier, mgorny
Differential Revision: https://reviews.llvm.org/D30751
llvm-svn: 311038
r310825 caused the clang-ppc64le-linux-lnt bot to go red
(http://lab.llvm.org:8011/builders/clang-ppc64le-linux-lnt/builds/5712)
because of a test-suite failure of
SingleSource/UnitTests/2003-07-09-SignedArgs
This reverts commit 0028f6a87224fb595a1c19c544cde9b003035996.
llvm-svn: 311008
Undef subreg definition means that the content of the super register
doesn't matter at this point. While that's true for virtual registers,
this may not hold when replacing them with actual physical registers.
Indeed, some part of the physical register may be coalesced with the
related virtual register and thus, the values for those parts matter and
must be live.
The fix consists in checking whether or not subregs of the physical register
being assigned to an undef subreg definition are live through that def and
insert an implicit use if they are. Doing so, will keep them alive until
that point like they should be.
E.g., let vreg14 being assigned to R0_R1 then
%vreg14:gsub_0<def,read-undef> = COPY %R0 ; <-- R1 is still live here
%vreg14:gsub_1<def> = COPY %R1
Before this changes, the rewriter would change the code into:
%R0<def> = KILL %R0, %R0_R1<imp-def> ; <-- this tells R1 is redefined
%R1<def> = KILL %R1, %R0_R1<imp-def>, %R0_R1<imp-use> ; this value of this R1
; is believed to come
; from the previous
; instruction
Because of this invalid liveness, later pass could make wrong choices and in
particular clobber live register as it happened with the register scavenger in
llvm.org/PR34107
Now we would generate:
%R0<def> = KILL %R0, %R0_R1<imp-def>, %R0_R1<imp-use> ; This tells R1 needs to
; reach this point
%R1<def> = KILL %R1, %R0_R1<imp-def>, %R0_R1<imp-use>
The bug has been here forever, it got exposed recently because the register
scavenger got smarter.
Fixes llvm.org/PR34107
llvm-svn: 310979
Summary:
This patch teaches PostDominatorTree about infinite loops. It is built on top of D29705 by @dberlin which includes a very detailed motivation for this change.
What's new is that the patch also teaches the incremental updater how to deal with reverse-unreachable regions and how to properly maintain and verify tree roots. Before that, the incremental algorithm sometimes ended up preserving reverse-unreachable regions after updates that wouldn't appear in the tree if it was constructed from scratch on the same CFG.
This patch makes the following assumptions:
- A sequence of updates should produce the same tree as a recalculating it.
- Any sequence of the same updates should lead to the same tree.
- Siblings and roots are unordered.
The last two properties are essential to efficiently perform batch updates in the future.
When it comes to the first one, we can decide later that the consistency between freshly built tree and an updated one doesn't matter match, as there are many correct ways to pick roots in infinite loops, and to relax this assumption. That should enable us to recalculate postdominators less frequently.
This patch is pretty conservative when it comes to incremental updates on reverse-unreachable regions and ends up recalculating the whole tree in many cases. It should be possible to improve the performance in many cases, if we decide that it's important enough.
That being said, my experiments showed that reverse-unreachable are very rare in the IR emitted by clang when bootstrapping clang. Here are the statistics I collected by analyzing IR between passes and after each removePredecessor call:
```
# functions: 52283
# samples: 337609
# reverse unreachable BBs: 216022
# BBs: 247840796
Percent reverse-unreachable: 0.08716159869015269 %
Max(PercRevUnreachable) in a function: 87.58620689655172 %
# > 25 % samples: 471 ( 0.1395104988314885 % samples )
... in 145 ( 0.27733680163724345 % functions )
```
Most of the reverse-unreachable regions come from invalid IR where it wouldn't be possible to construct a PostDomTree anyway.
I would like to commit this patch in the next week in order to be able to complete the work that depends on it before the end of my internship, so please don't wait long to voice your concerns :).
Reviewers: dberlin, sanjoy, grosser, brzycki, davide, chandlerc, hfinkel
Reviewed By: dberlin
Subscribers: nhaehnle, javed.absar, kparzysz, uabelho, jlebar, hiraditya, llvm-commits, dberlin, david2050
Differential Revision: https://reviews.llvm.org/D35851
llvm-svn: 310940
Summary:
This fixes PR32721 in IfConvertTriangle and possible similar problems in
IfConvertSimple, IfConvertDiamond and IfConvertForkedDiamond.
In PR32721 we had a triangle
EBB
| \
| |
| TBB
| /
FBB
where FBB didn't have any successors at all since it ended with an
unconditional return. Then TBB and FBB were be merged into EBB, but EBB
would still keep its successors, and the use of analyzeBranch and
CorrectExtraCFGEdges wouldn't help to remove them since the return
instruction is not analyzable (at least not on ARM).
The edge updating code and branch probability updating code is now pushed
into MergeBlocks() which allows us to share the same update logic between
more callsites. This lets us remove several dependencies on analyzeBranch
and completely eliminate RemoveExtraEdges.
One thing that showed up with this patch was that IfConversion sometimes
left a successor with 0% probability even if there was no branch or
fallthrough to the successor.
One such example from the test case ifcvt_bad_zero_prob_succ.mir. The
indirect branch tBRIND can only jump to bb.1, but without the patch we
got:
bb.0:
successors: %bb.1(0x80000000)
bb.1:
successors: %bb.1(0x80000000), %bb.2(0x00000000)
tBRIND %r1, 1, %cpsr
B %bb.1
bb.2:
There is no way to jump from bb.1 to bb2, but still there is a 0% edge
from bb.1 to bb.2.
With the patch applied we instead get the expected:
bb.0:
successors: %bb.1(0x80000000)
bb.1:
successors: %bb.1(0x80000000)
tBRIND %r1, 1, %cpsr
B %bb.1
Since bb.2 had no predecessor at all, it was removed.
Several testcases had to be updated due to this since the removed
successor made the "Branch Probability Basic Block Placement" pass
sometimes place blocks in a different order.
Finally added a couple of new test cases:
* PR32721_ifcvt_triangle_unanalyzable.mir:
Regression test for the original problem dexcribed in PR 32721.
* ifcvt_triangleWoCvtToNextEdge.mir:
Regression test for problem that caused a revert of my first attempt
to solve PR 32721.
* ifcvt_simple_bad_zero_prob_succ.mir:
Test case showing the problem where a wrong successor with 0% probability
was previously left.
* ifcvt_[diamond|forked_diamond|simple]_unanalyzable.mir
Very simple test cases for the simple and (forked) diamond cases
involving unanalyzable branches that can be nice to have as a base if
wanting to write more complicated tests.
Reviewers: iteratee, MatzeB, grosser, kparzysz
Reviewed By: kparzysz
Subscribers: kbarton, davide, aemerson, nemanjai, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D34099
llvm-svn: 310697
Clean up after my misguided attempt in r304267 to "fix" CMP_SWAP
returning an uninitialized status value.
- I was always using tMOVi8 to zero the status register which cannot
encode higher register numbers and llvm would silently miscompile)
- Nobody was ever looking at that status value outside the expansion.
ARMDAGToDAGISel::SelectCMP_SWAP() the only place creating CMP_SWAP
instructions was not mapping anything to it. (The cmpxchg status value
from llvm IR is lowered to a manual comparison after the CMP_SWAP)
So this:
- Renames the register from "status" to "temp" it make it obvious that
it isn't used outside the expansion.
- Remove the zeroing status/temp register.
- Keep the live-in list improvements from r304267
Fixes http://llvm.org/PR34056
llvm-svn: 310534
Summary:
A similar error message has been removed from the ARMTargetMachineBase
constructor in r306939. With this patch, we generate an error message
for the example below, compiled with -mcpu=cortex-m0, which does not
have ARM execution mode.
__attribute__((target("arm"))) int foo(int a, int b)
{
return a + b % a;
}
__attribute__((target("thumb"))) int bar(int a, int b)
{
return a + b % a;
}
By adding this error message to ARMBaseTargetMachine::getSubtargetImpl,
we can deal with functions that set -thumb-mode in target-features.
At the moment it seems like Clang does not have access to target-feature
specific information, so adding the error message to the frontend will
be harder.
Reviewers: echristo, richard.barton.arm, t.p.northover, rengolin, efriedma
Reviewed By: echristo, efriedma
Subscribers: efriedma, aemerson, javed.absar, kristof.beyls
Differential Revision: https://reviews.llvm.org/D35627
llvm-svn: 310486
Summary:
By removing FeatureNoARM implies ModeThumb, we can detect cases where a
function's target-features contain -thumb-mode (enables ARM codegen for the
function), but the architecture does not support ARM mode. Previously, the
implication caused the FeatureNoARM bit to be cleared for functions with
-thumb-mode, making the assertion in ARMSubtarget::ARMSubtarget [1]
pointless for such functions.
This assertion is the only guard against generating ARM code for
architectures without ARM codegen support. Is there a place where we
could easily generate error messages for the user? At the moment, we
would generate ARM code for Thumb-only architectures. X86 has the same
behavior as ARM, as in it only has an assertion and no error message,
but I think for ARM an error message would be helpful. What do you
think?
For the example below, `llc -mtriple=armv7m-eabi test.ll -o -` will
generate ARM assembler (or fail with an assertion error with this patch).
Note that if we run the resulting assembler through llvm-mc, we get
an appropriate error message, but not when codegen is handled
through clang.
```
define void @bar() #0 {
entry:
ret void
}
attributes #0 = { "target-features"="-thumb-mode" }
```
[1] c1f7b54cef/lib/Target/ARM/ARMSubtarget.cpp (L147)
Reviewers: t.p.northover, rengolin, peter.smith, aadg, silviu.baranga, richard.barton.arm, echristo
Reviewed By: rengolin, echristo
Subscribers: efriedma, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D35569
llvm-svn: 310476
Add support in the instruction selector for G_GLOBAL_VALUE for ELF and
MachO for the static relocation model. We don't handle Windows yet
because that's Thumb-only, and we don't handle Thumb in general at the
moment.
Support for PIC, ROPI, RWPI and TLS will be added in subsequent commits.
Differential Revision: https://reviews.llvm.org/D35883
llvm-svn: 309927
This patch:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) <- (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) <- (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRY into ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) -> C
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 309923
IMHO it is an antipattern to have a enum value that is Default.
At any given piece of code it is not clear if we have to handle
Default or if has already been mapped to a concrete value. In this
case in particular, only the target can do the mapping and it is nice
to make sure it is always done.
This deletes the two default enum values of CodeModel and uses an
explicit Optional<CodeModel> when it is possible that it is
unspecified.
llvm-svn: 309911
`llc -march` is problematic because it only switches the target
architecture, but leaves the operating system unchanged. This
occasionally leads to indeterministic tests because the OS from
LLVM_DEFAULT_TARGET_TRIPLE is used.
However we can simply always use `llc -mtriple` instead. This changes
all the tests to do this to avoid people using -march when they copy and
paste parts of tests.
See also the discussion in https://reviews.llvm.org/D35287
llvm-svn: 309755
In the last half-dozen commits to LLVM I removed code that became dead
after removing the offset parameter from llvm.dbg.value gradually
proceeding from IR towards the backend. Before I can move on to
DwarfDebug and friends there is one last side-called offset I need to
remove: This patch modifies PrologEpilogInserter's use of the
DBG_VALUE's offset argument to use a DIExpression instead. Because the
PrologEpilogInserter runs at the Machine level I had to play a little
trick with a named llvm.dbg.mir node to get the DIExpressions to print
in MIR dumps (which print the llvm::Module followed by the
MachineFunction dump).
I also had to add rudimentary DwarfExpression support to CodeView and
as a side-effect also fixed a bug (CodeViewDebug::collectVariableInfo
was supposed to give up on variables with complex DIExpressions, but
would fail to do so for fragments, which are also modeled as
DIExpressions).
With this last holdover removed we will have only one canonical way of
representing offsets to debug locations which will simplify the code
in DwarfDebug (and future versions of CodeViewDebug once it starts
handling more complex expressions) and make it easier to reason about.
This patch is NFC-ish: All test case changes are for assembler
comments and the binary output does not change.
rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D36125
llvm-svn: 309751
https://reviews.llvm.org/D31536 didn't really solve the problem it was
trying to solve; it got rid of the assertion failure, but we were still
scheduling the DAG incorrectly (mixing together instructions from
different calls), leading to a MachineVerifier failure.
In order to schedule the DAG correctly, we have to make sure we don't
schedule a node which should be blocked by an interference. Fix
ScheduleDAGRRList::PickNodeToScheduleBottomUp so it doesn't pick a node
like that.
The added call to FindAvailableNode() is the key change here; this makes
sure we don't try to schedule a call while we're in the middle of
scheduling a different call. I'm not sure this is the right approach; in
particular, I'm not sure how to prove we don't end up with an infinite
loop of repeatedly backtracking.
This also reverts the code change from D31536. It doesn't do anything
useful: we should never schedule an ADJCALLSTACKDOWN unless we've
already scheduled the corresponding ADJCALLSTACKUP.
Differential Revision: https://reviews.llvm.org/D33818
llvm-svn: 309642
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.
rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951
llvm-svn: 309426
This patch enables choice for accessing thread local
storage pointer (like '-mtp' in gcc).
Differential Revision: https://reviews.llvm.org/D34408
llvm-svn: 309381
The ARM Runtime ABI document (IHI0043) defines the AEABI floating point
helper functions in section 4.1.2 The floating-point helper functions.
The functions listed in this section must always use the base AAPCS calling
convention.
This test generates calls to all the helper functions that llvm supports
and checks that the base AAPCS calling convention has been used. We test
the equivalent of -mfloat-abi=soft, -mfloat-abi=softfp, -mfloat-abi=hardfp
with an FPU that supports single and double precision, and one that only
supports double precision.
Differential Revision: https://reviews.llvm.org/D35904
llvm-svn: 309371
The code assumed that unclobbered/unspilled callee saved registers are
unused in the function. This is not true for callee saved registers that are
also used to pass parameters such as swiftself.
rdar://33401922
llvm-svn: 309350
This patch cleans up and fixes issues in the M-Class system register handling:
1. It defines the system registers and the encoding (SYSm values) in one place:
a new ARMSystemRegister.td using SearchableTable, thereby removing the
hand-coded values which existed in multiple places.
2. Some system registers e.g. BASEPRI_MAX_NS which do not exist were being allowed!
Ref: ARMv6/7/8M architecture reference manual.
Reviewed by: @t.p.northover, @olist01, @john.brawn
Differential Revision: https://reviews.llvm.org/D35209
llvm-svn: 308456
Re-recommiting after landing DAG extension-crash fix.
Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.
Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.
Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.
Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.
The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.
Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand
Reviewed By: rnk
Subscribers: sdardis, nemanjai, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33345
llvm-svn: 308350
Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.
Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.
Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.
Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.
The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.
Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand
Reviewed By: rnk
Subscribers: sdardis, nemanjai, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33345
llvm-svn: 308025
Insert a TSTri to set the flags and a Bcc to branch based on their
values. This is a bit inefficient in the (common) cases where the
condition for the branch comes from a compare right before the branch,
since we set the flags both as part of the compare lowering and as part
of the branch lowering. We're going to live with that until we settle on
a principled way to handle this kind of situation, which occurs with
other patterns as well (combines might be the way forward here).
llvm-svn: 308009
This boils down to not crashing in reg bank select due to the lack of
register operands on this instruction, and adding some tests. The
instruction selection is already covered by the TableGen'erated code.
llvm-svn: 307904
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
llvm-svn: 307722
Use CHECK-NEXT for the comparison sequence, to make sure we don't get
any unexpected instructions in the middle of our flag manipulation
efforts.
llvm-svn: 307656
Make sure that all the legalizer tests where the original instruction
needs to be removed check for the removal. We do this by adding
CHECK-NOT lines before and after the replacement sequence. This won't
catch pathological cases where the instruction remains somewhere in the
middle of the instruction sequence that's supposed to replace it, but
hopefully that won't occur in practice (since ideally we'd be setting
the insert point for the new instruction sequence either before or after
the original instruction and not fiddle with it while building the
sequence).
llvm-svn: 307647
We used to forget to erase the original instruction when replacing a
G_FCMP true/false. Fix this bug and make sure the tests check for it.
llvm-svn: 307639
Reverting as it breaks tramp3d-v4 in the llvm test-suite. I added some
comments to https://reviews.llvm.org/D33345 about it.
This reverts commit r307546.
llvm-svn: 307589
Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.
Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.
Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.
The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.
Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand
Reviewed By: rnk
Subscribers: sdardis, nemanjai, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33345
llvm-svn: 307546
We lower to a sequence consisting of:
- MOVi 0 into a register
- VCMPS to do the actual comparison and set the VFP flags
- FMSTAT to move the flags out of the VFP unit
- MOVCCi to either use the "zero register" that we have previously set
with the MOVi, or move 1 into the result register, based on the values
of the flags
As was the case with soft-float, for some predicates (one, ueq) we
actually need two comparisons instead of just one. When that happens, we
generate two VCMPS-FMSTAT-MOVCCi sequences and chain them by means of
using the result of the first MOVCCi as the "zero register" for the
second one. This is a bit overkill, since one comparison followed by
two non-flag-setting conditional moves should be enough. In any case,
the backend manages to CSE one of the comparisons away so it doesn't
matter much.
Note that unlike SelectionDAG and FastISel, we always use VCMPS, and not
VCMPES. This makes the code a lot simpler, and it also seems correct
since the LLVM Lang Ref defines simple true/false returns if the
operands are QNaN's. For SNaN's, even VCMPS throws an Invalid Operand
exception, so they won't be slipping through unnoticed.
Implementation-wise, this introduces a template so we can share the same
code that we use for handling integer comparisons, since the only
differences are in the details (exact opcodes to be used etc). Hopefully
this will be easy to extend to s64 G_FCMP.
llvm-svn: 307365
When scavenging for a use in instruction MI, we will reload after
that instruction and hence cannot spill uses/defs of this instruction.
This fixes http://llvm.org/PR33687
llvm-svn: 307352
This covers both hard and soft float.
Hard float is easy, since it's just Legal.
Soft float is more involved, because there are several different ways to
handle it based on the predicate: one and ueq need not only one, but two
libcalls to get a result. Furthermore, we have large differences between
the values returned by the AEABI and GNU functions.
AEABI functions return a nice 1 or 0 representing true and respectively
false. GNU functions generally return a value that needs to be compared
against 0 (e.g. for ogt, the value returned by the libcall is > 0 for
true). We could introduce redundant comparisons for AEABI as well, but
they don't seem easy to remove afterwards, so we do different processing
based on whether or not the result really needs to be compared against
something (and just truncate if it doesn't).
llvm-svn: 307243
For two ROTR operations with shifts C1, C2; combined shift operand will be (C1 + C2) % bitsize.
Differential revision: https://reviews.llvm.org/D12833
llvm-svn: 307179
This enables us to ensure better LTO and code generation in the face of module linking.
Remove a report_fatal_error from the TargetMachine and replace it with an assert in ARMSubtarget - and remove the test that depended on the error. The assertion will still fire in the case that we were reporting before, but error reporting needs to be in front end tools if possible for options parsing.
llvm-svn: 306939
It looks like there are two target-independent but not GISel instructions that
need legalization, IMPLICIT_DEF and PHI. These are already anomalies since
their operands have important LLTs attached, so to make things more uniform it
seems like a good idea to add generic variants. Starting with G_IMPLICIT_DEF.
llvm-svn: 306875
On big-endian machines the high and low parts of the value accessed by ldrexd
and strexd are swapped around. To account for this we swap inputs and outputs
in ISelLowering.
Patch by Bharathi Seshadri.
llvm-svn: 306865
Summary:
TBB and THH allow using a Thumb GPR or the PC as destination operand.
A few machine verifier failures where due to those instructions not
expecting PC as destination operand.
Add -verify-machineinstrs to test/CodeGen/ARM/jump-table-tbh.ll to add
test coverage even if expensive checks are disabled.
Reviewers: MatzeB, t.p.northover, jmolloy
Reviewed By: MatzeB
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D34610
llvm-svn: 306654