Summary:
Re-factor some code to improve clarity and style based on review
comments from http://reviews.llvm.org/D18093.
Reviewers: MatzeB, mcrosier
Subscribers: MatzeB, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D19128
llvm-svn: 266372
Some SIMD implementations are not IEEE-754 compliant, for example ARM's NEON.
This patch teaches the loop vectorizer to only allow transformations of loops
that either contain no floating-point operations or have enough allowance
flags supporting lack of precision (ex. -ffast-math, Darwin).
For that, the target description now has a method which tells us if the
vectorizer is allowed to handle FP math without falling into unsafe
representations, plus a check on every FP instruction in the candidate loop
to check for the safety flags.
This commit makes LLVM behave like GCC with respect to ARM NEON support, but
it stops short of fixing the underlying problem: sub-normals. Neither GCC
nor LLVM have a flag for allowing sub-normal operations. Before this patch,
GCC only allows it using unsafe-math flags and LLVM allows it by default with
no way to turn it off (short of not using NEON at all).
As a first step, we push this change to make it safe and in sync with GCC.
The second step is to discuss a new sub-normal's flag on both communitues
and come up with a common solution. The third step is to improve the FastMath
flags in LLVM to encode sub-normals and use those flags to restrict NEON FP.
Fixes PR16275.
llvm-svn: 266363
https://llvm.org/bugs/show_bug.cgi?id=27105
We can check if all bits outside of a constant mask are set with a
single constant.
As noted in the bug report, although this form should be considered the
canonical IR, backends may want to transform this into an 'andn' / 'andc'
comparison against zero because that could be a single machine instruction.
Differential Revision: http://reviews.llvm.org/D18842
llvm-svn: 266362
Summary:
This adds the necessary target code to be able to run the ir translator.
Lowering function arguments and returns is a nop and there is no support
for RegBankSelect.
Reviewers: arsenm, qcolombet
Subscribers: arsenm, joker.eph, vkalintiris, llvm-commits
Differential Revision: http://reviews.llvm.org/D19077
llvm-svn: 266356
MachineInstr.h and MachineInstrBuilder.h are very popular headers,
widely included across all LLVM backends. It turns out that there only a
handful of TUs that actually care about DI operands on MachineInstrs.
After this change, touching DebugInfoMetadata.h and rebuilding llc only
needs 112 actions instead of 542.
llvm-svn: 266351
Summary:
If a PHI has an incoming undef, we can pretend that it is equal to one
non-undef, non-self incoming value.
This is particularly relevant in combination with the StructurizeCFG
pass, which introduces PHI nodes with undefs. Previously, this lead to
branch conditions that were uniform before StructurizeCFG to become
non-uniform afterwards, which confused the SIAnnotateControlFlow
pass.
This fixes a crash when Mesa radeonsi compiles a shader from
dEQP-GLES3.functional.shaders.switch.switch_in_for_loop_dynamic_vertex
Reviewers: arsenm, tstellarAMD, jingyue
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D19013
llvm-svn: 266347
Summary:
This fully solves the problem where the StructurizeCFG pass does not
consider the same branches as uniform as the SIAnnotateControlFlow pass.
The patch in D19013 helps with this problem, but is not sufficient
(and, interestingly, causes a "regression" with one of the existing
test cases).
No tests included here, because tests in D19013 already cover this.
Reviewers: arsenm, tstellarAMD
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D19018
llvm-svn: 266346
Summary:
This pass is unnecessary and overly conservative. It was motivated by
situations like
def %vreg0:SGPR_32
...
if-block:
..
def %vreg1:SGPR_32
...
else-block:
...
use %vreg0:SGPR_32
...
and similar situations with uses after the non-uniform control flow, where
we are not allowed to assign %vreg0 and %vreg1 to the same physical register,
even though in the original, thread/workitem-based CFG, it looks like the
live ranges of these registers do not overlap.
However, by the time register allocation runs, we have moved to a wave-based
CFG that accurately represents the fact that the wave may run through both
the if- and the else-block. So the live ranges of %vreg0 and %vreg1 already
overlap even without the SIFixSGPRLiveRanges pass.
In addition to proving this change correct, I have tested it with Piglit
and a small number of other tests.
Reviewers: arsenm, tstellarAMD
Subscribers: MatzeB, arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D19041
llvm-svn: 266345
Summary:
I've been carrying this change around with me for a while, because the if ()
managed to confuse me while following the code. All callers ensure that the
assertion holds.
Reviewers: arsenm, tstellarAMD
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D19042
llvm-svn: 266344
FastRegAlloc works only at the basic-block level and spills all live-out
registers. Unfortunately for a stack-based cmpxchg near the spill slots, this
can perpetually clear the exclusive monitor, which means the cmpxchg will never
succeed.
I believe the only way to handle this within LLVM is by expanding the loop
post-regalloc. We don't want this in general because it severely limits the
optimisations that can be done, so we limit this to -O0 compilations.
It's an ugly hack, and about the one good point in the whole mess is that we
can treat all cmpxchg operations in the most naive way possible (seq_cst, no
clrex faff) without affecting correctness.
Should fix PR25526.
llvm-svn: 266339
Summary:
For GL_ARB_compute_shader we need to support workgroup sizes of at least 1024. However, if we want to allow large workgroup sizes, we may need to use less registers, as we have to run more waves per SIMD.
This patch adds an attribute to specify the maximum work group size the compiled program needs to support. It defaults, to 256, as that has no wave restrictions.
Reducing the number of registers available is done similarly to how the registers were reserved for chips with the sgpr init bug.
Reviewers: mareko, arsenm, tstellarAMD, nhaehnle
Subscribers: FireBurn, kerberizer, llvm-commits, arsenm
Differential Revision: http://reviews.llvm.org/D18340
Patch By: Bas Nieuwenhuizen
llvm-svn: 266337
Summary:
The code previously always used s1 as it was using the user + system SGPR
information for compute kernels. This is incorrect for Mesa shaders though,
The register should be the next SGPR after all user and system SGPR's.
We use that Mesa adds arguments for all input and system SGPR's and
take the next available SGPR for the scratch wave offset register.
Signed-off-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewers: mareko, arsenm, nhaehnle, tstellarAMD
Subscribers: qcolombet, arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D18941
Patch By: Bas Nieuwenhuizen
llvm-svn: 266336
Summary:
Add a print method to Predicated Scalar Evolution which prints all interesting
transformations done by PSE.
Loop Access Analysis will now print this as part of the analysis output.
We now use this to check the exact expression transformations that were done
by PSE in LAA.
The additional checking also acts as white-box testing for the getAsAddRec method.
Reviewers: anemet, sanjoy
Subscribers: sanjoy, mzolotukhin, llvm-commits
Differential Revision: http://reviews.llvm.org/D18792
llvm-svn: 266334
Alias 'jic $reg, 0' to 'jrc $reg' and 'jialc $reg, 0' to 'jalrc $reg' like
binutils.
This patch was previous committed as r266055 as seemed to have caused some spurious
test failures. They did not reappear after further local testing.
llvm-svn: 266301
Summary:
The only difference between the removed tests and the pre-existing
ones, is the materialization of the zero constant, which shouldn't
matter for these cases.
Reviewers: dsanders, sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D18693
llvm-svn: 266285
The behavior of {MIN,MAX}NAN differs from that of {MIN,MAX}NUM when only
one of the inputs is NaN: -NUM will return the non-NaN argument while
-NAN would return NaN.
It is desirable to lower to @llvm.{min,max}num to -NAN if they don't
have a native instruction for -NUM. Notably, ARMv7 NEON's vmin has the
-NAN semantics.
N.B. Of course, it is only safe to do this if the intrinsic call is
marked nnan.
llvm-svn: 266279
This code was creating a new type in the global context, regardless
of which context the user is sitting in, what can possibly go wrong?
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266275
At some point, ARM stopped getting any benefit from ConstantHoisting because
the pass called a different variant of getIntImmCost. Reimplementing the
correct variant revealed some problems, however:
+ ConstantHoisting was modifying switch statements. This is simply invalid,
the cases must remain integer constants no matter the notional cost.
+ ConstantHoisting was mangling alloca instructions in the entry block. These
should be handled by FrameLowering, so constants actually have a cost of 0.
Worse, the resulting bitcasts meant they became dynamic allocas.
rdar://25707382
llvm-svn: 266260
Fix a major bug from r265456. Although it's now much rarer, ValueMapper
sometimes has to duplicate cycles. The
might-transitively-reference-a-temporary counts don't decrement on their
own when there are cycles, and you need to call MDNode::resolveCycles to
fix it.
r265456 was checking the input nodes to see if they were unresolved.
This is useless; they should never be unresolved. Instead we should
check the output nodes and resolve cycles on them.
llvm-svn: 266258
Summary: LLVMAttribute has outlived its utility and is becoming a problem for C API users that what to use all the LLVM attributes. In order to help moving away from LLVMAttribute in a smooth manner, this diff introduce LLVMGetAttrKindIDInContext, which can be used instead of the enum values.
Reviewers: Wallbraker, whitequark, joker.eph, echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18749
llvm-svn: 266257
An unsigned 2 bit bitfield takes 4 bytes in MSVC. Instead of a bitfield,
just use an unsigned char. We can go back to a bitfield when someone
implements the TODO of exposing and reusing the remaining 6 bits.
llvm-svn: 266256
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.
Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.
This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.
Differential Revision: http://reviews.llvm.org/D18901
llvm-svn: 266253
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.
Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.
This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.
Differential Revision: http://reviews.llvm.org/D18902
llvm-svn: 266252
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.
Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.
This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.
Differential Revision: http://reviews.llvm.org/D19007
llvm-svn: 266251
And update the existing test cases in test/Object/macho-invalid.test
to use llvm-objdump with the -macho option to produce these
error messages and stop producing the generic "Invalid data
was encountered while parsing the file" message.
Working from the beginning of the file, if the mach header is too large for
the size of the file and then if the load commands that follow extend past
the end of the file these two errors now generate correct error messages.
Both of these have existing test cases in test/Object/macho-invalid.test .
But the first with macho-invalid-header it will never trigger the error message
"mach header extends past the end of the file" using any of the llvm tools as
they all use identify_magic() which rejects files with the correct magic number
that are too small in size. So I tested this by hacking that code and seeing the
error message down in parseHeader() really does happen. So in case there
is ever code in llvm that directly calls createMachOObjectFile() this error
message will be correctly produced.
The second error message of "load commands extends past the end of the file"
is triggered by a number of existing tests cases in test/Object/macho-invalid.test .
Also other tests trigger different error messages now like "ilocalsym plus
nlocalsym in LC_DYSYMTAB load command extends past the end of the
symbol table".
There are two existing test cases that still get the "Invalid data was encountered ..."
error messages that I will tackle next. But they will involve a bit of pluming an
Expect<...> up through the call stack and I want to do those as separate changes.
FYI, for those test cases that were trying to test specific errors that now get
different errors I’ll fix those in follow on changes and create new test cases
for those so they test the error they were meant to test.
llvm-svn: 266248
Summary:
When we are spilling SGPRs to scratch memory, we usually don't have
free SGPRs to do the address calculation, so we need to re-use the
ScratchOffset register for the calculation.
Reviewers: arsenm
Subscribers: arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D18917
llvm-svn: 266244
A DISubprogram on x86_64 was 48 bytes. During an LTO build we
end up allocating *a lot* of these (see Duncan's numbers on
llvm-dev and/or my numbers in the review link).
This change reduces the size to 40 bytes, with a nice effect
on peak memory usage when LTO'ing clang.
There are more classes in the hierarchy which can be compacted
so more patches will come. DISubprogram was the biggest offender
in my profiling, anyway.
Differential Revision: http://reviews.llvm.org/D18918
llvm-svn: 266241
Since we can't emit diagnostics for missing "jmp 1f" labels until the end of
the file, we need to be able to restore the context used to calculate
file/line. This is basically the "# line file" directive that's being used at
the time the expression is seen.
rdar://25706972
llvm-svn: 266238
Geoff Berry