[llvm] r209643 - Convert some X86 blendv* intrinsics into IR.
Filipe Cabecinhas
me at filcab.net
Tue May 27 09:29:20 PDT 2014
Thanks for the comments.
Unfortunately I had the reverse select instruction. I'm committing the fix
as soon as the tests finish running.
Daniel, David: It didn't trigger warnings on the default compile of clang
for me, but you made me look again, so I added the parenthesis just in
case. I also ran clang-format, which I had forgotten.
Itia, Andrea: Indeed, I was doing the inverse select mask. I'll fix it in
the next commit.
Andrea: The patch was reviewed on-list but not on phab, it seems.
Thanks,
Filipe
On Tue, May 27, 2014 at 9:22 AM, David Blaikie <dblaikie at gmail.com> wrote:
> On Tue, May 27, 2014 at 3:08 AM, Daniel Jasper <djasper at google.com> wrote:
> >
> >
> >
> > On Tue, May 27, 2014 at 5:42 AM, Filipe Cabecinhas <me at filcab.net>
> wrote:
> >>
> >> Author: filcab
> >> Date: Mon May 26 22:42:20 2014
> >> New Revision: 209643
> >>
> >> URL: http://llvm.org/viewvc/llvm-project?rev=209643&view=rev
> >> Log:
> >> Convert some X86 blendv* intrinsics into IR.
> >>
> >> Summary:
> >> Implemented an InstCombine transformation that takes a blendv* intrinsic
> >> call and translates it into an IR select, if the mask is constant.
> >>
> >> This will eventually get lowered into blends with immediates if
> possible,
> >> or pblendvb (with an option to further optimize if we can transform the
> >> pblendvb into a blend+immediate instruction, depending on the selector).
> >> It will also enable optimizations by the IR passes, which give up on
> >> sight of the intrinsic.
> >>
> >> Both the transformation and the lowering of its result to asm got shiny
> >> new tests.
> >>
> >> The transformation is a bit convoluted because of blendvp[sd]'s
> >> definition:
> >>
> >> Its mask is a floating point value! This forces us to convert it and get
> >> the highest bit. I suppose this happened because the mask has type
> >> __m128 in Intel's intrinsic and v4sf (for blendps) in gcc's builtin.
> >>
> >> I will send an email to llvm-dev to discuss if we want to change this or
> >> not.
> >>
> >> Reviewers: grosbach, delena, nadav
> >>
> >> Differential Revision: http://reviews.llvm.org/D3859
> >>
> >> Added:
> >> llvm/trunk/test/CodeGen/X86/avx2-blend.ll
> >> llvm/trunk/test/Transforms/InstCombine/blend_x86.ll
> >> Modified:
> >> llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
> >> llvm/trunk/test/CodeGen/X86/avx-blend.ll
> >> llvm/trunk/test/CodeGen/X86/sse41-blend.ll
> >>
> >> Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
> >> URL:
> >>
> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp?rev=209643&r1=209642&r2=209643&view=diff
> >>
> >>
> ==============================================================================
> >> --- llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
> (original)
> >> +++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp Mon May
> 26
> >> 22:42:20 2014
> >> @@ -718,6 +718,41 @@ Instruction *InstCombiner::visitCallInst
> >> break;
> >> }
> >>
> >> + case Intrinsic::x86_sse41_pblendvb:
> >> + case Intrinsic::x86_sse41_blendvps:
> >> + case Intrinsic::x86_sse41_blendvpd:
> >> + case Intrinsic::x86_avx_blendv_ps_256:
> >> + case Intrinsic::x86_avx_blendv_pd_256:
> >> + case Intrinsic::x86_avx2_pblendvb: {
> >> + // Convert blendv* to vector selects if the mask is constant.
> >> + // This optimization is convoluted because the intrinsic is defined
> >> as
> >> + // getting a vector of floats or doubles for the ps and pd
> versions.
> >> + // FIXME: That should be changed.
> >> + Value *Mask = II->getArgOperand(2);
> >> + if (auto C = dyn_cast<ConstantDataVector>(Mask)) {
> >> + auto Tyi1 = Builder->getInt1Ty();
> >> + auto SelectorType = cast<VectorType>(Mask->getType());
> >> + auto EltTy = SelectorType->getElementType();
> >> + unsigned Size = SelectorType->getNumElements();
> >> + unsigned BitWidth = EltTy->isFloatTy() ? 32 :
> (EltTy->isDoubleTy()
> >> ? 64 : EltTy->getIntegerBitWidth());
> >> + assert(BitWidth == 64 || BitWidth == 32 || BitWidth == 8 &&
> "Wrong
> >> arguments for variable blend intrinsic");
> >
> >
> > This is assert is bad in that it triggers Clang's operator precedence
>
> Are you sure this triggered /Clang's/ warning? I was pretty sure
> Clang's warning had a suppression for this case, since it doesn't
> actually change the semantics of the condition.
>
> > warning and works correctly more or less by accident (consider the
> > precedence of || and && - with the string implicitly evaluating to true).
> > Fixed in r209648.
> >
> > Also, please adhere to LLVM coding standards (most importantly the 80
> column
> > limit).
> >
> >>
> >> + SmallVector<Constant*, 32> Selectors;
> >> + for (unsigned I = 0; I < Size; ++I) {
> >> + // The intrinsics only read the top bit
> >> + uint64_t Selector;
> >> + if (BitWidth == 8)
> >> + Selector = C->getElementAsInteger(I);
> >> + else
> >> + Selector =
> >> C->getElementAsAPFloat(I).bitcastToAPInt().getZExtValue();
> >> + Selectors.push_back(ConstantInt::get(Tyi1, Selector >>
> (BitWidth
> >> - 1)));
> >> + }
> >> + auto NewSelector = ConstantVector::get(Selectors);
> >> + return SelectInst::Create(NewSelector, II->getArgOperand(0),
> >> II->getArgOperand(1), "blendv");
> >> + } else {
> >> + break;
> >> + }
> >> + }
> >> +
> >> case Intrinsic::x86_avx_vpermilvar_ps:
> >> case Intrinsic::x86_avx_vpermilvar_ps_256:
> >> case Intrinsic::x86_avx_vpermilvar_pd:
> >>
> >> Modified: llvm/trunk/test/CodeGen/X86/avx-blend.ll
> >> URL:
> >>
> http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx-blend.ll?rev=209643&r1=209642&r2=209643&view=diff
> >>
> >>
> ==============================================================================
> >> --- llvm/trunk/test/CodeGen/X86/avx-blend.ll (original)
> >> +++ llvm/trunk/test/CodeGen/X86/avx-blend.ll Mon May 26 22:42:20 2014
> >> @@ -135,3 +135,26 @@ define <2 x double> @testb(<2 x double>
> >> %min = select <2 x i1> %min_is_x, <2 x double> %x, <2 x double> %y
> >> ret <2 x double> %min
> >> }
> >> +
> >> +; If we can figure out a blend has a constant mask, we should emit the
> >> +; blend instruction with an immediate mask
> >> +define <4 x double> @constant_blendvpd_avx(<4 x double> %xy, <4 x
> double>
> >> %ab) {
> >> +; CHECK-LABEL: constant_blendvpd_avx:
> >> +; CHECK-NOT: mov
> >> +; CHECK: vblendpd
> >> +; CHECK: ret
> >> + %1 = select <4 x i1> <i1 false, i1 false, i1 true, i1 false>, <4 x
> >> double> %xy, <4 x double> %ab
> >> + ret <4 x double> %1
> >> +}
> >> +
> >> +define <8 x float> @constant_blendvps_avx(<8 x float> %xyzw, <8 x
> float>
> >> %abcd) {
> >> +; CHECK-LABEL: constant_blendvps_avx:
> >> +; CHECK-NOT: mov
> >> +; CHECK: vblendps
> >> +; CHECK: ret
> >> + %1 = select <8 x i1> <i1 false, i1 false, i1 false, i1 true, i1
> false,
> >> i1 false, i1 false, i1 true>, <8 x float> %xyzw, <8 x float> %abcd
> >> + ret <8 x float> %1
> >> +}
> >> +
> >> +declare <8 x float> @llvm.x86.avx.blendv.ps.256(<8 x float>, <8 x
> float>,
> >> <8 x float>)
> >> +declare <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double>, <4 x
> >> double>, <4 x double>)
> >>
> >> Added: llvm/trunk/test/CodeGen/X86/avx2-blend.ll
> >> URL:
> >>
> http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx2-blend.ll?rev=209643&view=auto
> >>
> >>
> ==============================================================================
> >> --- llvm/trunk/test/CodeGen/X86/avx2-blend.ll (added)
> >> +++ llvm/trunk/test/CodeGen/X86/avx2-blend.ll Mon May 26 22:42:20 2014
> >> @@ -0,0 +1,11 @@
> >> +; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=core-avx2 |
> FileCheck
> >> %s
> >> +
> >> +define <32 x i8> @constant_pblendvb_avx2(<32 x i8> %xyzw, <32 x i8>
> >> %abcd) {
> >> +; CHECK-LABEL: constant_pblendvb_avx2:
> >> +; CHECK: vmovdqa
> >> +; CHECK: vpblendvb
> >> + %1 = select <32 x i1> <i1 false, i1 false, i1 true, i1 false, i1
> true,
> >> i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1 false, i1
> true,
> >> i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1 false, i1
> true,
> >> i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1 false, i1
> true,
> >> i1 true, i1 true, i1 false>, <32 x i8> %xyzw, <32 x i8> %abcd
> >> + ret <32 x i8> %1
> >> +}
> >> +
> >> +declare <32 x i8> @llvm.x86.avx2.pblendvb(<32 x i8>, <32 x i8>, <32 x
> >> i8>)
> >>
> >> Modified: llvm/trunk/test/CodeGen/X86/sse41-blend.ll
> >> URL:
> >>
> http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/sse41-blend.ll?rev=209643&r1=209642&r2=209643&view=diff
> >>
> >>
> ==============================================================================
> >> --- llvm/trunk/test/CodeGen/X86/sse41-blend.ll (original)
> >> +++ llvm/trunk/test/CodeGen/X86/sse41-blend.ll Mon May 26 22:42:20 2014
> >> @@ -88,3 +88,35 @@ entry:
> >> store double %extract214vector_func.i, double addrspace(1)* undef,
> >> align 8
> >> ret void
> >> }
> >> +
> >> +; If we can figure out a blend has a constant mask, we should emit the
> >> +; blend instruction with an immediate mask
> >> +define <2 x double> @constant_blendvpd(<2 x double> %xy, <2 x double>
> >> %ab) {
> >> +; In this case, we emit a simple movss
> >> +; CHECK-LABEL: constant_blendvpd
> >> +; CHECK: movsd
> >> +; CHECK: ret
> >> + %1 = select <2 x i1> <i1 true, i1 false>, <2 x double> %xy, <2 x
> >> double> %ab
> >> + ret <2 x double> %1
> >> +}
> >> +
> >> +define <4 x float> @constant_blendvps(<4 x float> %xyzw, <4 x float>
> >> %abcd) {
> >> +; CHECK-LABEL: constant_blendvps
> >> +; CHECK-NOT: mov
> >> +; CHECK: blendps $7
> >> +; CHECK: ret
> >> + %1 = select <4 x i1> <i1 false, i1 false, i1 false, i1 true>, <4 x
> >> float> %xyzw, <4 x float> %abcd
> >> + ret <4 x float> %1
> >> +}
> >> +
> >> +define <16 x i8> @constant_pblendvb(<16 x i8> %xyzw, <16 x i8> %abcd) {
> >> +; CHECK-LABEL: constant_pblendvb:
> >> +; CHECK: movaps
> >> +; CHECK: pblendvb
> >> +; CHECK: ret
> >> + %1 = select <16 x i1> <i1 false, i1 false, i1 true, i1 false, i1
> true,
> >> i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1 false, i1
> true,
> >> i1 true, i1 true, i1 false>, <16 x i8> %xyzw, <16 x i8> %abcd
> >> + ret <16 x i8> %1
> >> +}
> >> +declare <16 x i8> @llvm.x86.sse41.pblendvb(<16 x i8>, <16 x i8>, <16 x
> >> i8>)
> >> +declare <4 x float> @llvm.x86.sse41.blendvps(<4 x float>, <4 x float>,
> <4
> >> x float>)
> >> +declare <2 x double> @llvm.x86.sse41.blendvpd(<2 x double>, <2 x
> double>,
> >> <2 x double>)
> >>
> >> Added: llvm/trunk/test/Transforms/InstCombine/blend_x86.ll
> >> URL:
> >>
> http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/blend_x86.ll?rev=209643&view=auto
> >>
> >>
> ==============================================================================
> >> --- llvm/trunk/test/Transforms/InstCombine/blend_x86.ll (added)
> >> +++ llvm/trunk/test/Transforms/InstCombine/blend_x86.ll Mon May 26
> >> 22:42:20 2014
> >> @@ -0,0 +1,56 @@
> >> +; RUN: opt < %s -instcombine -mtriple=x86_64-apple-macosx
> -mcpu=core-avx2
> >> -S | FileCheck %s
> >> +
> >> +define <2 x double> @constant_blendvpd(<2 x double> %xy, <2 x double>
> >> %ab) {
> >> +; CHECK-LABEL: @constant_blendvpd
> >> +; CHECK: select <2 x i1> <i1 true, i1 false>
> >> + %1 = tail call <2 x double> @llvm.x86.sse41.blendvpd(<2 x double>
> %xy,
> >> <2 x double> %ab, <2 x double> <double 0xFFFFFFFFE0000000, double
> >> 0.000000e+00>)
> >> + ret <2 x double> %1
> >> +}
> >> +
> >> +define <4 x float> @constant_blendvps(<4 x float> %xyzw, <4 x float>
> >> %abcd) {
> >> +; CHECK-LABEL: @constant_blendvps
> >> +; CHECK: select <4 x i1> <i1 false, i1 false, i1 false, i1 true>
> >> + %1 = tail call <4 x float> @llvm.x86.sse41.blendvps(<4 x float>
> %xyzw,
> >> <4 x float> %abcd, <4 x float> <float 0.000000e+00, float 0.000000e+00,
> >> float 0.000000e+00, float 0xFFFFFFFFE0000000>)
> >> + ret <4 x float> %1
> >> +}
> >> +
> >> +define <16 x i8> @constant_pblendvb(<16 x i8> %xyzw, <16 x i8> %abcd) {
> >> +; CHECK-LABEL: @constant_pblendvb
> >> +; CHECK: select <16 x i1> <i1 false, i1 false, i1 true, i1 false, i1
> >> true, i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1
> false, i1
> >> true, i1 true, i1 true, i1 false>
> >> + %1 = tail call <16 x i8> @llvm.x86.sse41.pblendvb(<16 x i8> %xyzw,
> <16
> >> x i8> %abcd, <16 x i8> <i8 0, i8 0, i8 255, i8 0, i8 255, i8 255, i8
> 255, i8
> >> 0, i8 0, i8 0, i8 255, i8 0, i8 255, i8 255, i8 255, i8 0>)
> >> + ret <16 x i8> %1
> >> +}
> >> +
> >> +define <4 x double> @constant_blendvpd_avx(<4 x double> %xy, <4 x
> double>
> >> %ab) {
> >> +; CHECK-LABEL: @constant_blendvpd_avx
> >> +; CHECK: select <4 x i1> <i1 true, i1 false, i1 true, i1 false>
> >> + %1 = tail call <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double>
> >> %xy, <4 x double> %ab, <4 x double> <double 0xFFFFFFFFE0000000, double
> >> 0.000000e+00, double 0xFFFFFFFFE0000000, double 0.000000e+00>)
> >> + ret <4 x double> %1
> >> +}
> >> +
> >> +define <8 x float> @constant_blendvps_avx(<8 x float> %xyzw, <8 x
> float>
> >> %abcd) {
> >> +; CHECK-LABEL: @constant_blendvps_avx
> >> +; CHECK: select <8 x i1> <i1 false, i1 false, i1 false, i1 true, i1
> >> false, i1 false, i1 false, i1 true>
> >> + %1 = tail call <8 x float> @llvm.x86.avx.blendv.ps.256(<8 x float>
> >> %xyzw, <8 x float> %abcd, <8 x float> <float 0.000000e+00, float
> >> 0.000000e+00, float 0.000000e+00, float 0xFFFFFFFFE0000000, float
> >> 0.000000e+00, float 0.000000e+00, float 0.000000e+00, float
> >> 0xFFFFFFFFE0000000>)
> >> + ret <8 x float> %1
> >> +}
> >> +
> >> +define <32 x i8> @constant_pblendvb_avx2(<32 x i8> %xyzw, <32 x i8>
> >> %abcd) {
> >> +; CHECK-LABEL: @constant_pblendvb_avx2
> >> +; CHECK: select <32 x i1> <i1 false, i1 false, i1 true, i1 false, i1
> >> true, i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1
> false, i1
> >> true, i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1
> false, i1
> >> true, i1 true, i1 true, i1 false, i1 false, i1 false, i1 true, i1
> false, i1
> >> true, i1 true, i1 true, i1 false>
> >> + %1 = tail call <32 x i8> @llvm.x86.avx2.pblendvb(<32 x i8> %xyzw,
> <32 x
> >> i8> %abcd,
> >> + <32 x i8> <i8 0, i8 0, i8 255, i8 0, i8 255, i8 255, i8 255, i8
> >> 0,
> >> + i8 0, i8 0, i8 255, i8 0, i8 255, i8 255, i8 255, i8
> >> 0,
> >> + i8 0, i8 0, i8 255, i8 0, i8 255, i8 255, i8 255, i8
> >> 0,
> >> + i8 0, i8 0, i8 255, i8 0, i8 255, i8 255, i8 255, i8
> >> 0>)
> >> + ret <32 x i8> %1
> >> +}
> >> +
> >> +declare <16 x i8> @llvm.x86.sse41.pblendvb(<16 x i8>, <16 x i8>, <16 x
> >> i8>)
> >> +declare <4 x float> @llvm.x86.sse41.blendvps(<4 x float>, <4 x float>,
> <4
> >> x float>)
> >> +declare <2 x double> @llvm.x86.sse41.blendvpd(<2 x double>, <2 x
> double>,
> >> <2 x double>)
> >> +
> >> +declare <32 x i8> @llvm.x86.avx2.pblendvb(<32 x i8>, <32 x i8>, <32 x
> >> i8>)
> >> +declare <8 x float> @llvm.x86.avx.blendv.ps.256(<8 x float>, <8 x
> float>,
> >> <8 x float>)
> >> +declare <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double>, <4 x
> >> double>, <4 x double>)
> >> +
> >>
> >>
> >> _______________________________________________
> >> llvm-commits mailing list
> >> llvm-commits at cs.uiuc.edu
> >> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
> >
> >
> >
> > _______________________________________________
> > llvm-commits mailing list
> > llvm-commits at cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
> >
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20140527/cb9222a6/attachment.html>
More information about the llvm-commits
mailing list