When materializing constant i1 values, they must be zero extended. We represent
i1 values as [0, 1], not [0, -1], in i32 registers. As it turns out, this code
path was dead for i1 values prior to r216006 (which is why this did not manifest in
miscompiles until recently).
Fixes -O0 self-hosting on PPC64/Linux.
llvm-svn: 224842
Correct the line information generation for preprocessed assembly. Although we
tracked the source information for the macro instantiation, we failed to account
for the fact that we were instantiating a macro, which is populated into a new
buffer and that the line information would be relative to the definition rather
than the actual instantiation location. This could cause the line number
associated with the statement to be very high due to wrapping of the difference
calculated for the preprocessor line information emitted into the stream.
Properly calculate the line for the macro instantiation, referencing the line
where the macro is actually used as GCC/gas do.
The test case uses x86, though the same problem exists on any other target using
the LLVM IAS.
llvm-svn: 224810
Patch by Ramkumar Ramachandra <artagnon@gmail.com>.
Also remove Llvm_executionengine.get_pointer_to_global, as it
is actually deprecated and didn't appear in a stable release.
llvm-svn: 224801
On non-Darwin PPC64, the TOC reload needs to come directly after the bctrl
instruction (for indirect calls) because the 'bctrl/ld 2, 40(1)' instruction
sequence is interpreted by the unwinding code in libgcc. To make sure these
occur as a pair, as with other pairings interpreted by the linker, fuse the two
instructions into one instruction (for code generation only).
In the future, we might wish to do this by emitting CFI directives instead,
but this solution is simpler, and mirrors what GCC does. Additional discussion
on this point is contained in the PR.
Fixes PR22015.
llvm-svn: 224788
GlobalAlias handling used to be after GlobalValue handling, which meant it was, in practice, dead code. r220165 moved GlobalAlias handling to be before GlobalValue handling, but also moved it to be before the max depth check, causing an assert due to a recursion depth limit violation.
This moves GlobalAlias handling forward to where it's safe, and changes the GlobalValue handling to only look at GlobalObjects.
Differential Revision: http://reviews.llvm.org/D6758
llvm-svn: 224765
It is tempting to mark the fixed stack slot used to store the return address as
immutable when lowering @llvm.returnaddress(i32 0). Unfortunately, within the
function, it is not completely immutable: it is written during the function
prologue. When using post-RA instruction scheduling, the prologue instructions
are available for scheduling, and we're not free to interchange the order of a
particular store in the prologue with loads from that stack location.
Fixes PR21976.
llvm-svn: 224761
In r224033, in moving the signed power-of-2 division expansion into
BuildSDIVPow2, I accidentally made it possible to attempt the lowering for a
64-bit division on PPC32. This later asserts.
Fixes PR21928.
llvm-svn: 224758
- Fix the case where more than 1 common instructions derived from the same
operand cannot be sunk. When a pair of value has more than 1 derived values
in both branches, only 1 derived value could be sunk.
- Replace BB1 -> (BB2, PN) map with joint value map, i.e.
map of (BB1, BB2) -> PN, which is more accurate to track common ops.
llvm-svn: 224757
r223862/r224203 tried to also combine base-updating load/stores.
There was a mistake there: the alignment was added as is as an operand to
the ARMISD::VLD/VST node. However, the VLD/VST selection logic doesn't care
about less-than-standard alignment attributes.
For example, no matter the alignment of a v2i64 load (say 1), SelectVLD picks
VLD1q64 (because of the memory type). But VLD1q64 ("vld1.64 {dXX, dYY}") is
8-aligned, per ARMARMv7a 3.2.1.
For the 1-aligned load, what we really want is VLD1q8.
This commit introduces bitcasts if necessary, and changes the vld/vst type to
one whose standard alignment matches the original load/store alignment.
Differential Revision: http://reviews.llvm.org/D6759
llvm-svn: 224754
fragmented variables.
This caused codegen to start crashing when we built somewhat large
programs with debug info and optimizations. 'check-msan' hit in, and
I suspect a bootstrap would as well. I mailed a test case to the
review thread.
llvm-svn: 224750
When combining consecutive loads+inserts into a single vector load,
we should keep the alignment of the base load. Doing otherwise can, and does,
lead to using overly aligned instructions. In the included test case, for
example, using a 32-byte vmovaps on a 16-byte aligned value. Oops.
rdar://19190968
llvm-svn: 224746
Previously I tried to plug musttail into the existing vararg lowering
code. That turned out to be a mistake, because non-vararg calls use
significantly different register lowering, even on x86. For example, AVX
vectors are usually passed in registers to normal functions and memory
to vararg functions. Now musttail uses a completely separate lowering.
Hopefully this can be used as the basis for non-x86 perfect forwarding.
Reviewers: majnemer
Differential Revision: http://reviews.llvm.org/D6156
llvm-svn: 224745
Followup to r224294:
ARM/AArch64: Attach the FrameSetup MIFlag to CFI instructions.
Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.
llvm-svn: 224743
Take two disjoint Loops L1 and L2.
LoopSimplify fails to simplify some loops (e.g. when indirect branches
are involved). In such situations, it can happen that an exit for L1 is
the header of L2. Thus, when we create PHIs in one of such exits we are
also inserting PHIs in L2 header.
This could break LCSSA form for L2 because these inserted PHIs can also
have uses in L2 exits, which are never handled in the current
implementation. Provide a fix for this corner case and test that we
don't assert/crash on that.
Differential Revision: http://reviews.llvm.org/D6624
rdar://problem/19166231
llvm-svn: 224740
This allows us to generate debug info for extremely advanced code such as
typedef struct { long int a; int b;} S;
int foo(S s) {
return s.b;
}
which at -O1 on x86_64 is codegen'd into
define i32 @foo(i64 %s.coerce0, i32 %s.coerce1) #0 {
ret i32 %s.coerce1, !dbg !24
}
with this patch we emit the following debug info for this
TAG_formal_parameter [3]
AT_location( 0x00000000
0x0000000000000000 - 0x0000000000000006: rdi, piece 0x00000008, rsi, piece 0x00000004
0x0000000000000006 - 0x0000000000000008: rdi, piece 0x00000008, rax, piece 0x00000004 )
AT_name( "s" )
AT_decl_file( "/Volumes/Data/llvm/_build.ninja.release/test.c" )
Thanks to chandlerc, dblaikie, and echristo for their feedback on all
previous iterations of this patch!
llvm-svn: 224739
Previously we assumed the section name had the form .text$foo, which is
what we used to do for inline functions. If the dollar wasn't present,
we'd put unwind data in the .pdata and .xdata sections for the main
.text section, which is incorrect.
Fixes PR22001.
llvm-svn: 224738
Currently, when ctpop is supported for scalar types, the expansion of
@llvm.ctpop.vXiY uses vector element extractions, insertions and individual
calls to @llvm.ctpop.iY. When not, expansion with bit-math operations is used
for the scalar calls.
Local haswell measurements show that we can improve vector @llvm.ctpop.vXiY
expansion in some cases by using a using a vector parallel bit twiddling
approach, based on:
v = v - ((v >> 1) & 0x55555555);
v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
v = ((v + (v >> 4) & 0xF0F0F0F)
v = v + (v >> 8)
v = v + (v >> 16)
v = v & 0x0000003F
(from http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel)
When scalar ctpop isn't supported, the approach above performs better for
v2i64, v4i32, v4i64 and v8i32 (see numbers below). And even when scalar ctpop
is supported, this approach performs ~2x better for v8i32.
Here, x86_64 implies -march=corei7-avx without ctpop and x86_64h includes ctpop
support with -march=core-avx2.
== [x86_64h - new]
v8i32: 0.661685
v4i32: 0.514678
v4i64: 0.652009
v2i64: 0.324289
== [x86_64h - old]
v8i32: 1.29578
v4i32: 0.528807
v4i64: 0.65981
v2i64: 0.330707
== [x86_64 - new]
v8i32: 1.003
v4i32: 0.656273
v4i64: 1.11711
v2i64: 0.754064
== [x86_64 - old]
v8i32: 2.34886
v4i32: 1.72053
v4i64: 1.41086
v2i64: 1.0244
More work for other vector types will come next.
llvm-svn: 224725
Extend the existing code which handles this for zext. This makes this
more useful for targets with ZeroOrNegativeOne BooleanContent and
obsoletes a custom combine SI uses for i1 setcc (sext(i1), 0, setne)
since the constant will now be shrunk to i1.
llvm-svn: 224691
The ARM ARM states:
LDM/LDMIA/LDMFD:
The SP can be in the list. However, ARM deprecates using these instructions
with SP in the list.
ARM deprecates using these instructions with both the LR and the PC in the
list.
LDMDA/LDMFA/LDMDB/LDMEA/LDMIB/LDMED:
The SP can be in the list. However, instructions that include the SP in the
list are deprecated.
Instructions that include both the LR and the PC in the list are deprecated.
POP:
The SP can only be in the list before ARMv7. ARM deprecates any use of ARM
instructions that include the SP, and the value of the SP after such an
instruction is UNKNOWN.
ARM deprecates the use of this instruction with both the LR and the PC in
the list.
Attempt to diagnose use of deprecated forms of these instructions. This mirrors
the previous changes to diagnose use of the deprecated forms of STM in ARM mode.
llvm-svn: 224682
(X & INT_MIN) ? X & INT_MAX : X into X & INT_MAX
(X & INT_MIN) ? X : X & INT_MAX into X
(X & INT_MIN) ? X | INT_MIN : X into X
(X & INT_MIN) ? X : X | INT_MIN into X | INT_MIN
llvm-svn: 224669
the error message for a bogus processor, and then look specifically for
that error message using FileCheck.
I actually tried to write the test this way at first, but drew a blank
on how to ensure the error message stayed in sync (oops). Now that I've
recalled how to do that, this is clearly better.
It also fixes an issue with a malloc implementation that actually prints
to stderr in all cases, which was causing problems for some builders it
seems.
llvm-svn: 224665
It is intended to be used for a family of personality functions that
have similar IR preparation requirements. Typically when interoperating
with MSVC personality functions, bits of functionality need to be
outlined from the main function into helper functions. There is also
usually more than one landing pad per invoke, which does not match the
LLVM IR landingpad representation.
None of this is implemented yet. This change just adds a new enum that
is active for *-windows-msvc and delegates to the EH removal preparation
pass. No functionality change for other targets.
llvm-svn: 224625
mubuf instructions now define the soffset field using the SCSrc_32
register class which indicates that only SGPRs and inline constants
are allowed.
llvm-svn: 224622
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. Also, fix code to also return the modified switch when only
the truncation is performed.
This fixes an assertion crash.
Differential Revision: http://reviews.llvm.org/D6644
rdar://problem/19191835
llvm-svn: 224588
Backends recognize (-0.0 - X) as the canonical form for fneg
and produce better code. Eg, ppc64 with 0.0:
lis r2, ha16(LCPI0_0)
lfs f0, lo16(LCPI0_0)(r2)
fsubs f1, f0, f1
blr
vs. -0.0:
fneg f1, f1
blr
Differential Revision: http://reviews.llvm.org/D6723
llvm-svn: 224583
Reverts commit r224574 to appease buildbots:
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. This fixes an assertion crash.
llvm-svn: 224576
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. This fixes an assertion crash.
Differential Revision: http://reviews.llvm.org/D6644
rdar://problem/19191835
llvm-svn: 224574
Summary: This fixes the exports iterator if the export list is empty.
Reviewers: Bigcheese, kledzik
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6732
llvm-svn: 224563
Fix bugs related to atomic microMIPS SC/LL instructions: While expanding atomic
operations the mips32r2 encoding was emitted instead of microMIPS.
Differential Revision: http://reviews.llvm.org/D6659
llvm-svn: 224524
Fix an off-by-one access introduced in 224502 for push.w and pop.w with single
register operands. Add test cases for both scenarios.
Thanks to Asiri Rathnayake for pointing out the failure!
llvm-svn: 224521
Summary:
Improve comments and remove a redundant attribute list.
There are no functional changes (to the CHECK's or to the code).
Part of these changes were suggested in http://reviews.llvm.org/D6637.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6705
llvm-svn: 224517
Added RegOp2MemOpTable4 to transform 4th operand from register to memory in merge-masked versions of instructions.
Added lowering tests.
llvm-svn: 224516
The ARM Architecture Reference Manual states the following:
LDM{,IA,DB}:
The SP cannot be in the list.
The PC can be in the list.
If the PC is in the list:
• the LR must not be in the list
• the instruction must be either outside any IT block, or the last
instruction in an IT block.
POP:
The PC can be in the list.
If the PC is in the list:
• the LR must not be in the list
• the instruction must be either outside any IT block, or the last
instruction in an IT block.
PUSH:
The SP and PC can be in the list in ARM instructions, but not in Thumb
instructions.
STM:{,IA,DB}:
The SP and PC can be in the list in ARM instructions, but not in Thumb
instructions.
llvm-svn: 224502
of the abi we should be using. For targets that don't use the
option there's no change, otherwise this allows external users
to set the ABI via string and avoid some of the -backend-option
pain in clang.
Use this option to move the ABI for the ARM port from the
Subtarget to the TargetMachine and update the testcases
accordingly since it's no longer valid to set via -mattr.
llvm-svn: 224492
same. This will change the "bare metal" ABI from APCS to AAPCS.
The only difference between the front and back end code is that
the code for Triple::GNU was added for environment. That will migrate
to the front end shortly.
Tests updated with the ABI they were originally testing in the case
of bare metal (e.g. -mtriple armv7) or with a -gnu for arm-linux
triples.
llvm-svn: 224489
This reverts commit r224416, reapplying r224389. The buildbots hadn't
recovered after my revert, waiting until David reverted a couple of his
commits. It looks like it was just bad timing (where we were both
modifying code related to the same assertion). Trying again...
Here's the original text:
When a function gets replaced by `ModuleLinker`, drop superseded
subprograms. This ensures that the "first" subprogram pointing at a
function is the same one that `!dbg` references point at.
This is a stop-gap fix for PR21910. Notably, this fixes Release+Asserts
bootstraps that are currently asserting out in
`LexicalScopes::initialize()` due to the explicit instantiations in
`lib/IR/Dominators.cpp` eventually getting replaced by -argpromotion.
llvm-svn: 224487
Also corrected the name of the load command to not end in an ’S’ as well as corrected
the name of the MachO::linker_option_command struct and other places that had the
word option as plural which did not match the Mac OS X headers.
llvm-svn: 224485
Summary:
With isSingleValueType starting to treat vector types as single-value types,
code that uses this interface needs to be updated.
Test Plan:
vector-global.ll
nvcl-param-align.ll
Reviewers: jholewinski
Reviewed By: jholewinski
Subscribers: llvm-commits, meheff, eliben, jholewinski
Differential Revision: http://reviews.llvm.org/D6573
llvm-svn: 224440
This handles the case of a BUILD_VECTOR being constructed out of elements extracted from a vector twice the size of the result vector. Previously this was always scalarized. Now, we try to construct a shuffle node that feeds on extract_subvectors.
This fixes PR15872 and provides a partial fix for PR21711.
Differential Revision: http://reviews.llvm.org/D6678
llvm-svn: 224429
Summary:
When generating MIPS assembly, LLVM always overrides the default assembler options by emitting the '.set noreorder', '.set nomacro' and '.set noat' directives,
while GCC uses the default options if an assembly-level function contains inline assembly code.
This becomes a problem when the code generated by LLVM is interleaved with inline assembly which assumes GCC-like assembler options (from Linux, for example).
This patch fixes these conflicts by setting the appropriate assembler options at the beginning of an inline asm block and popping them at the end.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6637
llvm-svn: 224425
Some intrinsics, like s/uadd.with.overflow and umul.with.overflow, are already strength reduced.
This change adds other arithmetic intrinsics: s/usub.with.overflow, smul.with.overflow.
It completes the work on PR20194.
llvm-svn: 224417
Summary:
Currently, it supports generating, but not parsing, this expression.
Test added as well.
Test Plan: New test added, no regressions due to this.
Reviewers: hfinkel
Reviewed By: hfinkel
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6672
llvm-svn: 224415
Add coverage in `llvm-lto` for the API exposed by libLTO to create
modules in local contexts.
The goal here isn't to test the symbol-related API extensively, just to
confirm that these modules work at all. (I'll be shifting code around
soon that should be NFC and I realized there was no test coverage.)
llvm-svn: 224408
We can always choose an value for undef which might cause %V to shift
out an important bit except for one case, when %V is zero.
However, shl behaves like an identity function when the right hand side
is zero.
llvm-svn: 224405
The type promotion helper does not support vector type, so when make
such it does not kick in in such cases.
Original commit message:
[CodeGenPrepare] Move sign/zero extensions near loads using type promotion.
This patch extends the optimization in CodeGenPrepare that moves a sign/zero
extension near a load when the target can combine them. The optimization may
promote any operations between the extension and the load to make that possible.
Although this optimization may be beneficial for all targets, in particular
AArch64, this is enabled for X86 only as I have not benchmarked it for other
targets yet.
** Context **
Most targets feature extended loads, i.e., loads that perform a zero or sign
extension for free. In that context it is interesting to expose such pattern in
CodeGenPrepare so that the instruction selection pass can form such loads.
Sometimes, this pattern is blocked because of instructions between the load and
the extension. When those instructions are promotable to the extended type, we
can expose this pattern.
** Motivating Example **
Let us consider an example:
define void @foo(i8* %addr1, i32* %addr2, i8 %a, i32 %b) {
%ld = load i8* %addr1
%zextld = zext i8 %ld to i32
%ld2 = load i32* %addr2
%add = add nsw i32 %ld2, %zextld
%sextadd = sext i32 %add to i64
%zexta = zext i8 %a to i32
%addza = add nsw i32 %zexta, %zextld
%sextaddza = sext i32 %addza to i64
%addb = add nsw i32 %b, %zextld
%sextaddb = sext i32 %addb to i64
call void @dummy(i64 %sextadd, i64 %sextaddza, i64 %sextaddb)
ret void
}
As it is, this IR generates the following assembly on x86_64:
[...]
movzbl (%rdi), %eax # zero-extended load
movl (%rsi), %es # plain load
addl %eax, %esi # 32-bit add
movslq %esi, %rdi # sign extend the result of add
movzbl %dl, %edx # zero extend the first argument
addl %eax, %edx # 32-bit add
movslq %edx, %rsi # sign extend the result of add
addl %eax, %ecx # 32-bit add
movslq %ecx, %rdx # sign extend the result of add
[...]
The throughput of this sequence is 7.45 cycles on Ivy Bridge according to IACA.
Now, by promoting the additions to form more extended loads we would generate:
[...]
movzbl (%rdi), %eax # zero-extended load
movslq (%rsi), %rdi # sign-extended load
addq %rax, %rdi # 64-bit add
movzbl %dl, %esi # zero extend the first argument
addq %rax, %rsi # 64-bit add
movslq %ecx, %rdx # sign extend the second argument
addq %rax, %rdx # 64-bit add
[...]
The throughput of this sequence is 6.15 cycles on Ivy Bridge according to IACA.
This kind of sequences happen a lot on code using 32-bit indexes on 64-bit
architectures.
Note: The throughput numbers are similar on Sandy Bridge and Haswell.
** Proposed Solution **
To avoid the penalty of all these sign/zero extensions, we merge them in the
loads at the beginning of the chain of computation by promoting all the chain of
computation on the extended type. The promotion is done if and only if we do not
introduce new extensions, i.e., if we do not degrade the code quality.
To achieve this, we extend the existing “move ext to load” optimization with the
promotion mechanism introduced to match larger patterns for addressing mode
(r200947).
The idea of this extension is to perform the following transformation:
ext(promotableInst1(...(promotableInstN(load))))
=>
promotedInst1(...(promotedInstN(ext(load))))
The promotion mechanism in that optimization is enabled by a new TargetLowering
switch, which is off by default. In other words, by default, the optimization
performs the “move ext to load” optimization as it was before this patch.
** Performance **
Configuration: x86_64: Ivy Bridge fixed at 2900MHz running OS X 10.10.
Tested Optimization Levels: O3/Os
Tests: llvm-testsuite + externals.
Results:
- No regression beside noise.
- Improvements:
CINT2006/473.astar: ~2%
Benchmarks/PAQ8p: ~2%
Misc/perlin: ~3%
The results are consistent for both O3 and Os.
<rdar://problem/18310086>
llvm-svn: 224402
SwitchInst::getNumCases() returns unsinged, so using uint64_t to count cases
seems unnecessary.
Also fix a missing CHECK in the test case.
llvm-svn: 224393
When a function gets replaced by `ModuleLinker`, drop superseded
subprograms. This ensures that the "first" subprogram pointing at a
function is the same one that `!dbg` references point at.
This is a stop-gap fix for PR21910. Notably, this fixes Release+Asserts
bootstraps that are currently asserting out in
`LexicalScopes::initialize()` due to the explicit instantiations in
`lib/IR/Dominators.cpp` eventually getting replaced by -argpromotion.
llvm-svn: 224389
Added a missing memory folding relationship for the (V)CVTPD2PS instruction - we can safely fold these for stack reloads.
Differential Revision: http://reviews.llvm.org/D6663
llvm-svn: 224383
SelectionDAG::isConsecutiveLoad() was not detecting consecutive loads
when the first load was offset from a base address.
This patch recognizes that pattern and subtracts the offset before comparing
the second load to see if it is consecutive.
The codegen change in the new test case improves from:
vmovsd 32(%rdi), %xmm0
vmovsd 48(%rdi), %xmm1
vmovhpd 56(%rdi), %xmm1, %xmm1
vmovhpd 40(%rdi), %xmm0, %xmm0
vinsertf128 $1, %xmm1, %ymm0, %ymm0
To:
vmovups 32(%rdi), %ymm0
An existing test case is also improved from:
vmovsd (%rdi), %xmm0
vmovsd 16(%rdi), %xmm1
vmovsd 24(%rdi), %xmm2
vunpcklpd %xmm2, %xmm0, %xmm0 ## xmm0 = xmm0[0],xmm2[0]
vmovhpd 8(%rdi), %xmm1, %xmm3
To:
vmovsd (%rdi), %xmm0
vmovsd 16(%rdi), %xmm1
vmovhpd 24(%rdi), %xmm0, %xmm0
vmovhpd 8(%rdi), %xmm1, %xmm1
This patch fixes PR21771 ( http://llvm.org/bugs/show_bug.cgi?id=21771 ).
Differential Revision: http://reviews.llvm.org/D6642
llvm-svn: 224379
Summary: As a side-quest for D6629 jvoung pointed out that I should use -verify-machineinstrs and this found a bug in x86-32's handling of EFLAGS for PUSHF/POPF. This patch fixes the use/def, and adds -verify-machineinstrs to all x86 tests which contain 'EFLAGS'. One exception: this patch leaves inline-asm-fpstack.ll as-is because it fails -verify-machineinstrs in a way unrelated to EFLAGS. This patch also modifies cmpxchg-clobber-flags.ll along the lines of what D6629 already does by also testing i386.
Test Plan: ninja check
Reviewers: t.p.northover, jvoung
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6687
llvm-svn: 224359
This patch extends the optimization in CodeGenPrepare that moves a sign/zero
extension near a load when the target can combine them. The optimization may
promote any operations between the extension and the load to make that possible.
Although this optimization may be beneficial for all targets, in particular
AArch64, this is enabled for X86 only as I have not benchmarked it for other
targets yet.
** Context **
Most targets feature extended loads, i.e., loads that perform a zero or sign
extension for free. In that context it is interesting to expose such pattern in
CodeGenPrepare so that the instruction selection pass can form such loads.
Sometimes, this pattern is blocked because of instructions between the load and
the extension. When those instructions are promotable to the extended type, we
can expose this pattern.
** Motivating Example **
Let us consider an example:
define void @foo(i8* %addr1, i32* %addr2, i8 %a, i32 %b) {
%ld = load i8* %addr1
%zextld = zext i8 %ld to i32
%ld2 = load i32* %addr2
%add = add nsw i32 %ld2, %zextld
%sextadd = sext i32 %add to i64
%zexta = zext i8 %a to i32
%addza = add nsw i32 %zexta, %zextld
%sextaddza = sext i32 %addza to i64
%addb = add nsw i32 %b, %zextld
%sextaddb = sext i32 %addb to i64
call void @dummy(i64 %sextadd, i64 %sextaddza, i64 %sextaddb)
ret void
}
As it is, this IR generates the following assembly on x86_64:
[...]
movzbl (%rdi), %eax # zero-extended load
movl (%rsi), %es # plain load
addl %eax, %esi # 32-bit add
movslq %esi, %rdi # sign extend the result of add
movzbl %dl, %edx # zero extend the first argument
addl %eax, %edx # 32-bit add
movslq %edx, %rsi # sign extend the result of add
addl %eax, %ecx # 32-bit add
movslq %ecx, %rdx # sign extend the result of add
[...]
The throughput of this sequence is 7.45 cycles on Ivy Bridge according to IACA.
Now, by promoting the additions to form more extended loads we would generate:
[...]
movzbl (%rdi), %eax # zero-extended load
movslq (%rsi), %rdi # sign-extended load
addq %rax, %rdi # 64-bit add
movzbl %dl, %esi # zero extend the first argument
addq %rax, %rsi # 64-bit add
movslq %ecx, %rdx # sign extend the second argument
addq %rax, %rdx # 64-bit add
[...]
The throughput of this sequence is 6.15 cycles on Ivy Bridge according to IACA.
This kind of sequences happen a lot on code using 32-bit indexes on 64-bit
architectures.
Note: The throughput numbers are similar on Sandy Bridge and Haswell.
** Proposed Solution **
To avoid the penalty of all these sign/zero extensions, we merge them in the
loads at the beginning of the chain of computation by promoting all the chain of
computation on the extended type. The promotion is done if and only if we do not
introduce new extensions, i.e., if we do not degrade the code quality.
To achieve this, we extend the existing “move ext to load” optimization with the
promotion mechanism introduced to match larger patterns for addressing mode
(r200947).
The idea of this extension is to perform the following transformation:
ext(promotableInst1(...(promotableInstN(load))))
=>
promotedInst1(...(promotedInstN(ext(load))))
The promotion mechanism in that optimization is enabled by a new TargetLowering
switch, which is off by default. In other words, by default, the optimization
performs the “move ext to load” optimization as it was before this patch.
** Performance **
Configuration: x86_64: Ivy Bridge fixed at 2900MHz running OS X 10.10.
Tested Optimization Levels: O3/Os
Tests: llvm-testsuite + externals.
Results:
- No regression beside noise.
- Improvements:
CINT2006/473.astar: ~2%
Benchmarks/PAQ8p: ~2%
Misc/perlin: ~3%
The results are consistent for both O3 and Os.
<rdar://problem/18310086>
llvm-svn: 224351
On X86, the Intel asm parser tries to match all memory operand sizes when
none is explicitly specified. For LEA, which doesn't really have a memory
operand (just a pointer one), this results in multiple successful matches,
one for each memory size. There's no error because it's same opcode, so
really, it's just one match. However, the tablegen'd matcher function
adds opcode/operands to the passed MCInst, and this results in multiple
duplicated operands.
This commit clears the MCInst in the tablegen'd matcher function.
We sometimes clear it when the match failed, so there's no expectation of
keeping the previous content anyway.
Differential Revision: http://reviews.llvm.org/D6670
llvm-svn: 224347
This is a fix for PR21709 ( http://llvm.org/bugs/show_bug.cgi?id=21709 ).
When we have 2 consecutive 16-byte loads that are merged into one 32-byte vector,
we can use a single 32-byte load instead.
But we don't do this for SandyBridge / IvyBridge because they have slower 32-byte memops.
We also don't bother using 32-byte *integer* loads on a machine that only has AVX1 (btver2)
because those operands would have to be split in half anyway since there is no support for
32-byte integer math ops.
Differential Revision: http://reviews.llvm.org/D6492
llvm-svn: 224344
The loop vectorizer optimizes loops containing conditional memory
accesses by generating masked load and store intrinsics.
This decision is target dependent.
http://reviews.llvm.org/D6527
llvm-svn: 224334
This test was missing a `Debug Info Version` so it's `not grep` was
passing vacuously. Update it to CHECK for something useful at the same
time so it doesn't bitrot quite so easily in the future.
llvm-svn: 224324
The use of SP and PC in the register list for stores is deprecated on ARM
(ARM ARM A.8.8.199):
ARM deprecates the use of ARM instructions that include the SP or the PC in
the list.
Provide a deprecation warning from the assembler in the case that the syntax is
ever seen.
llvm-svn: 224319
The PowerPC backend, somewhat embarrassingly, did not generate an
optimal-length sequence of instructions for a 32-bit bswap. While adding a
pattern for the bswap intrinsic to fix this would not have been terribly
difficult, doing so would not have addressed the real problem: we had been
generating poor code for many bit-permuting operations (by which I mean things
like byte-swap that permute the bits of one or more inputs around in various
ways). Here are some initial steps toward solving this deficiency.
Bit-permuting operations are represented, at the SDAG level, using ISD::ROTL,
SHL, SRL, AND and OR (mostly with constant second operands). Looking back
through these operations, we can build up a description of the bits in the
resulting value in terms of bits of one or more input values (and constant
zeros). For each bit, we compute the rotation amount from the original value,
and then group consecutive (value, rotation factor) bits into groups. Groups
sharing these attributes are then collected and sorted, and we can then
instruction select the entire permutation using a combination of masked
rotations (rlwinm), imm ands (andi/andis), and masked rotation inserts
(rlwimi).
The result is that instead of lowering an i32 bswap as:
rlwinm 5, 3, 24, 16, 23
rlwinm 4, 3, 24, 0, 7
rlwimi 4, 3, 8, 8, 15
rlwimi 5, 3, 8, 24, 31
rlwimi 4, 5, 0, 16, 31
we now produce:
rlwinm 4, 3, 8, 0, 31
rlwimi 4, 3, 24, 16, 23
rlwimi 4, 3, 24, 0, 7
and for the 'test6' example in the PowerPC/README.txt file:
unsigned test6(unsigned x) {
return ((x & 0x00FF0000) >> 16) | ((x & 0x000000FF) << 16);
}
we used to produce:
lis 4, 255
rlwinm 3, 3, 16, 0, 31
ori 4, 4, 255
and 3, 3, 4
and now we produce:
rlwinm 4, 3, 16, 24, 31
rlwimi 4, 3, 16, 8, 15
and, as a nice bonus, this fixes the FIXME in
test/CodeGen/PowerPC/rlwimi-and.ll.
This commit does not include instruction-selection for i64 operations, those
will come later.
llvm-svn: 224318
Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.
llvm-svn: 224294
isKnownPredicate.
The motivation for this change is to optimize away checks in loops
like this:
limit = min(t, len)
for (i = 0 to limit)
if (i >= len || i < 0) throw_array_of_of_bounds();
a[i] = ...
Differential Revision: http://reviews.llvm.org/D6635
llvm-svn: 224285
Summary: x86 allows either ordering for the LOCK and DATA16 prefixes, but using GCC+GAS leads to different code generation than using LLVM. This change matches the order that GAS emits the x86 prefixes when a semicolon isn't used in inline assembly (see tc-i386.c comment before define LOCK_PREFIX), and helps simplify tooling that operates on the instruction's byte sequence (such as NaCl's validator). This change shouldn't have any performance impact.
Test Plan: ninja check
Reviewers: craig.topper, jvoung
Subscribers: jfb, llvm-commits
Differential Revision: http://reviews.llvm.org/D6630
llvm-svn: 224283
Now that `Metadata` is typeless, reflect that in the assembly. These
are the matching assembly changes for the metadata/value split in
r223802.
- Only use the `metadata` type when referencing metadata from a call
intrinsic -- i.e., only when it's used as a `Value`.
- Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
when referencing it from call intrinsics.
So, assembly like this:
define @foo(i32 %v) {
call void @llvm.foo(metadata !{i32 %v}, metadata !0)
call void @llvm.foo(metadata !{i32 7}, metadata !0)
call void @llvm.foo(metadata !1, metadata !0)
call void @llvm.foo(metadata !3, metadata !0)
call void @llvm.foo(metadata !{metadata !3}, metadata !0)
ret void, !bar !2
}
!0 = metadata !{metadata !2}
!1 = metadata !{i32* @global}
!2 = metadata !{metadata !3}
!3 = metadata !{}
turns into this:
define @foo(i32 %v) {
call void @llvm.foo(metadata i32 %v, metadata !0)
call void @llvm.foo(metadata i32 7, metadata !0)
call void @llvm.foo(metadata i32* @global, metadata !0)
call void @llvm.foo(metadata !3, metadata !0)
call void @llvm.foo(metadata !{!3}, metadata !0)
ret void, !bar !2
}
!0 = !{!2}
!1 = !{i32* @global}
!2 = !{!3}
!3 = !{}
I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines). I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.
This is part of PR21532.
llvm-svn: 224257
Adds the various "rm" instruction variants into the list of instructions that have a partial register update. Also adds all variants of SQRTSD that were missing in the original list.
Differential Revision: http://reviews.llvm.org/D6620
llvm-svn: 224246
PPCTargetLowering::DAGCombineExtBoolTrunc contains logic to remove unwanted
truncations and extensions when dealing with nodes of the form:
zext(binary-ops(binary-ops(trunc(x), trunc(y)), ...)
There was a FIXME in the implementation (now removed) regarding the fact that
the function would abort the transformations if any of the non-output operands
of a SELECT or SELECT_CC node would need to be promoted (because they were
also output operands, for example). As a result, we continued to generate
unnecessary zero-extends for code such as this:
unsigned foo(unsigned a, unsigned b) {
return (a <= b) ? a : b;
}
which would produce:
cmplw 0, 3, 4
isel 3, 4, 3, 1
rldicl 3, 3, 0, 32
blr
and now we produce:
cmplw 0, 3, 4
isel 3, 4, 3, 1
blr
which is better in the obvious way.
llvm-svn: 224213
r223862 tried to also combine base-updating load/stores.
r224198 reverted it, as "it created a regression on the test-suite
on test MultiSource/Benchmarks/Ptrdist/anagram by scrambling the order
in which the words are shown."
Reapply, with a fix to ignore non-normal load/stores.
Truncstores are handled elsewhere (you can actually write a pattern for
those, whereas for postinc loads you can't, since they return two values),
but it should be possible to also combine extloads base updates, by checking
that the memory (rather than result) type is of the same size as the addend.
Original commit message:
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.
We can do the same thing for generic load/stores.
Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).
Differential Revision: http://reviews.llvm.org/D6585
llvm-svn: 224203
This reverts commit r223862, as it created a regression on the test-suite
on test MultiSource/Benchmarks/Ptrdist/anagram by scrambling the order
in which the words are shown. We'll investigate the issue and re-apply
when safe.
llvm-svn: 224198
options.
This commit changes the command line arguments (PassInfo::PassArgument) of two
passes, MachineFunctionPrinter and MachineScheduler, to avoid collisions with
command line options that have the same argument strings.
This bug manifests when the PassList construct (defined in opt.cpp) is used
in a tool that links with codegen passes. To reproduce the bug, paste the
following lines into llc.cpp and run llc.
#include "llvm/IR/LegacyPassNameParser.h"
static llvm:🆑:list<const llvm::PassInfo*, bool, llvm::PassNameParser>
PassList(llvm:🆑:desc("Optimizations available:"));
rdar://problem/19212448
llvm-svn: 224186
On PPC64, we end up with lots of i32 -> i64 zero extensions, not only from all
of the usual places, but also from the ABI, which specifies that values passed
are zero extended. Almost all 32-bit PPC instructions in PPC64 mode are defined
to do *something* to the higher-order bits, and for some instructions, that
action clears those bits (thus providing a zero-extended result). This is
especially common after rotate-and-mask instructions. Adding an additional
instruction to zero-extend the results of these instructions is unnecessary.
This PPCISelDAGToDAG peephole optimization examines these zero-extensions, and
looks back through their operands to see if all instructions will implicitly
zero extend their results. If so, we convert these instructions to their 64-bit
variants (which is an internal change only, the actual encoding of these
instructions is the same as the original 32-bit ones) and remove the
unnecessary zero-extension (changing where the INSERT_SUBREG instructions are
to make everything internally consistent).
llvm-svn: 224169
I saw a failure on an internal bot, opened this file, saw it was missing,
thought "aha!", tried to land, got an "file is out of date", synced, didn't see
the file listed right above the line I added (cause I didn't add it in the
right place) and landed. Apologies!
llvm-svn: 224152
The goal of this tool is to replicate Darwin's dsymutil functionality
based on LLVM. dsymutil is a DWARF linker. Darwin's linker (ld64) does
not link the debug information, it leaves it in the object files in
relocatable form, but embbeds a `debug map` into the executable that
describes where to find the debug information and how to relocate it.
When releasing/archiving a binary, dsymutil is called to link all the DWARF
information into a `dsym bundle` that can distributed/stored along with
the binary.
With this commit, the LLVM based dsymutil is just able to parse the STABS
debug maps embedded by ld64 in linked binaries (and not all of them, for
example archives aren't supported yet).
Note that the tool directory is called dsymutil, but the executable is
currently called llvm-dsymutil. This discrepancy will disappear once the
tool will be feature complete. At this point the executable will be renamed
to dsymutil, but until then you do not want it to override the system one.
Differential Revision: http://reviews.llvm.org/D6242
llvm-svn: 224134
Summary:
This commit enables the MIPS-III target and adds support for code
generation of SELECT nodes. We have to use pseudo-instructions with
custom inserters for these nodes as MIPS-III CPUs do not have
conditional-move instructions.
Depends on D6212
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6464
llvm-svn: 224128
This reapplies r224118 with a fix for test 'misched-code-difference-with-debug.ll'.
That test was failing on some buildbots because it was x86 specific but it was
missing a target triple.
Added an explicit triple to test misched-code-difference-with-debug.ll.
llvm-svn: 224126
Summary:
For Mips targets that do not have conditional-move instructions, ie. targets
before MIPS32 and MIPS-IV, we have to insert a diamond control-flow
pattern in order to support SELECT nodes. In order to do that, we add
pseudo-instructions with a custom inserter that emits the necessary
control-flow that selects the correct value.
With this patch we add complete support for code generation of Mips-II targets
based on the LLVM test-suite.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6212
llvm-svn: 224124
This patch fixes the issue reported as PR21807. There was a minor difference
in the generated code depending on the -g flag.
The cause was that with -g the machine scheduler used a different
scheduling strategy. This decision was based on the number of instructions
in a schedule region and included debug instructions in that count.
This patch fixes the issue in MISched and provides a test.
Patch by Russell Gallop!
llvm-svn: 224118
The __fp16 type is unconditionally exposed. Since -mfp16-format is not yet
supported, there is not a user switch to change this behaviour. This build
attribute should capture the default behaviour of the compiler, which is to
expose the IEEE 754 version of __fp16.
When -mfp16-format is emitted, that will be the way to control the value of
this build attribute.
Change-Id: I8a46641ff0fd2ef8ad0af5f482a6d1af2ac3f6b0
llvm-svn: 224115
DW_OP_const <const> doesn't describe a constant value, but a value at a constant address.
The proper way to describe a constant value is DW_OP_constu <const>, DW_OP_stack_value.
Added DW_OP_stack_value to the stack.
Marked incorrect-variable-debugloc1.ll to xfail for PowerPC64, while the the failure (PR21881)
is being investigated.
llvm-svn: 224098
Summary:
InstCombine infinite-loops for the testcase added
It is because InstCombine is generating instructions that can be
optimized by itself. Fix by not optimizing frem if the optimized
type is the same as original type.
rdar://problem/19150820
Reviewers: majnemer
Differential Revision: http://reviews.llvm.org/D6634
llvm-svn: 224097
The returned operand needs to be permuted for the unordered
compares. Also fix incorrectly producing fmin_legacy / fmax_legacy
for f64, which don't exist.
llvm-svn: 224094
This is nice for the instruction patterns, but it complicates
min / max matching. The select doesn't have the correct type and would
require looking through the bitcasts for the real float operands.
llvm-svn: 224092
Add an option to disable optimization to shrink truncated larger type
loads to smaller type loads. On SI this prevents using scalar load
instructions in some cases, since there are no scalar extloads.
llvm-svn: 224084
`MDString`s can have arbitrary characters in them. Prevent an assertion
that fired in `BitcodeWriter` because of sign extension by copying the
characters into the record as `unsigned char`s.
Based on a patch by Keno Fischer; fixes PR21882.
llvm-svn: 224077
This reflects the typelessness of `Metadata` in the bitcode format,
removing types from all metadata operands.
`METADATA_VALUE` represents a `ValueAsMetadata`, and always has two
fields: the type and the value.
`METADATA_NODE` represents an `MDNode`, and unlike `METADATA_OLD_NODE`,
doesn't store types. It stores operands at their ID+1 so that `0` can
reference `nullptr` operands.
Part of PR21532.
llvm-svn: 224073
If we have an add (or an or that is really an add), where one operand is a
FrameIndex and the other operand is a small constant, we can combine the
lowering of the FrameIndex (which is lowered as an add of the FI and a zero
offset) with the constant operand.
Amusingly, this is an old potential improvement entry from
lib/Target/PowerPC/README.txt which had never been resolved. In short, we used
to lower:
%X = alloca { i32, i32 }
%Y = getelementptr {i32,i32}* %X, i32 0, i32 1
ret i32* %Y
as:
addi 3, 1, -8
ori 3, 3, 4
blr
and now we produce:
addi 3, 1, -4
blr
which is much more sensible.
llvm-svn: 224071
This commit changes the way we get fake stack from ASan runtime
(to find use-after-return errors) and the way we represent local
variables:
- __asan_stack_malloc function now returns pointer to newly allocated
fake stack frame, or NULL if frame cannot be allocated. It doesn't
take pointer to real stack as an input argument, it is calculated
inside the runtime.
- __asan_stack_free function doesn't take pointer to real stack as
an input argument. Now this function is never called if fake stack
frame wasn't allocated.
- __asan_init version is bumped to reflect changes in the ABI.
- new flag "-asan-stack-dynamic-alloca" allows to store all the
function local variables in a dynamic alloca, instead of the static
one. It reduces the stack space usage in use-after-return mode
(dynamic alloca will not be called if the local variables are stored
in a fake stack), and improves the debug info quality for local
variables (they will not be described relatively to %rbp/%rsp, which
are assumed to be clobbered by function calls). This flag is turned
off by default for now, but I plan to turn it on after more
testing.
llvm-svn: 224062
This patch teaches the instruction combiner how to fold a call to 'insertqi' if
the 'length field' (3rd operand) is set to zero, and if the sum between
field 'length' and 'bit index' (4th operand) is bigger than 64.
From the AMD64 Architecture Programmer's Manual:
1. If the sum of the bit index + length field is greater than 64, then the
results are undefined;
2. A value of zero in the field length is defined as a length of 64.
This patch improves the existing combining logic for intrinsic 'insertqi'
adding extra checks to address both point 1. and point 2.
Differential Revision: http://reviews.llvm.org/D6583
llvm-svn: 224054
PPCISelDAGToDAG contained existing code to lower i32 sdiv by a power-of-2 using
srawi/addze, but did not implement the i64 case. DAGCombine now contains a
callback specifically designed for this purpose (BuildSDIVPow2), and part of
the logic has been moved to an implementation of that callback. Doing this
lowering using BuildSDIVPow2 likely does not matter, compared to handling
everything in PPCISelDAGToDAG, for the positive divisor case, but the negative
divisor case, which generates an additional negation, can potentially benefit
from additional folding from DAGCombine. Now, both the i32 and the i64 cases
have been implemented.
Fixes PR20732.
llvm-svn: 224033
Canonicalize formatting of metadata to make it easier to upgrade via
scripts -- in particular, one line per metadata definition makes it more
`sed`-able.
This is preparation for changing the assembly syntax for metadata [1].
[1]: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20141208/248449.html
llvm-svn: 224002
The test is failing for llvm-ppc64 because for this platform the location list is not being generated at all (most likely because of the bug in PPC code optimization or generation). I will file a bug agains PPC compiler, but meanwhile, until PPC bug is fixed, I will have to revert my change.
llvm-svn: 224000
Quite a major error here: the expansions for the Pseudos with and without
folded load were mixed up. Fortunately it only affects ARM-mode, when not using
movw/movt, on Darwin. I'm guessing no-one actually uses that combination.
llvm-svn: 223986
DW_OP_const <const> doesn't describe a constant value, but a value at a constant address.
The proper way to describe a constant value is DW_OP_constu <const>, DW_OP_stack_value.
Added DW_OP_stack_value to the stack.
-This line, and those below, will be ignored--
M lib/CodeGen/AsmPrinter/DwarfDebug.cpp
A test/DebugInfo/incorrect-variable-debugloc1.ll
llvm-svn: 223981
In the large code model we have to first get the address of the GOT entry, load
the address of the constant, and then load the constant itself.
To avoid these loads and the GOT entry alltogether this commit changes the way
how FP constants are materialized in the large code model. The constats are now
materialized in a GPR and then bitconverted/moved into the FPR.
Reviewed by Tim Northover
Fixes rdar://problem/16572564.
llvm-svn: 223941
Add patterns to match SSE (shufpd) and AVX (vpermilpd) shuffle codegen
when storing the high element of a v2f64. The existing patterns were
only checking for an unpckh type of shuffle.
http://llvm.org/bugs/show_bug.cgi?id=21791
Differential Revision: http://reviews.llvm.org/D6586
llvm-svn: 223929
EltsFromConsecutiveLoads was apparently only ever called for 128-bit vectors, and assumed this implicitly. r223518 started calling it for AVX-sized vectors, causing the code path that had this assumption to crash.
This adds a check to make this path fire only for 128-bit vectors.
Differential Revision: http://reviews.llvm.org/D6579
llvm-svn: 223922
As indicated by the tests, it is possible to feed the AsmParser an
invalid datalayout string. We should verify the result of parsing this
string regardless of whether or not we have assertions enabled.
llvm-svn: 223898
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.
We can do the same thing for generic load/stores.
Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).
Differential Revision: http://reviews.llvm.org/D6585
llvm-svn: 223862
It was missing from the VLD1/VST1 handling logic, even though the
corresponding instructions exist (same form as v2i64).
In preparation for a future patch.
llvm-svn: 223832
The load/store value type is currently not available when lowering the memcpy
intrinsic. Add the missing nullptr check to support this in 'computeAddress'.
Fixes rdar://problem/19178947.
llvm-svn: 223818
Colin LeMahieu