[FastISel][X86] Add support for cvttss2si/cvttsd2si intrinsics.

This adds support for the cvttss2si/cvttsd2si intrinsics. Preceding
insertelement instructions are folded into the conversion instruction (if
possible).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210870 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Juergen Ributzka 2014-06-13 02:21:58 +00:00
parent 6b0a08b15b
commit e431884ed7
2 changed files with 120 additions and 0 deletions

View File

@ -1962,6 +1962,72 @@ bool X86FastISel::X86VisitIntrinsicCall(const IntrinsicInst &I) {
UpdateValueMap(&I, ResultReg, 2);
return true;
}
case Intrinsic::x86_sse_cvttss2si:
case Intrinsic::x86_sse_cvttss2si64:
case Intrinsic::x86_sse2_cvttsd2si:
case Intrinsic::x86_sse2_cvttsd2si64: {
bool IsInputDouble;
switch (I.getIntrinsicID()) {
default: llvm_unreachable("Unexpected intrinsic.");
case Intrinsic::x86_sse_cvttss2si:
case Intrinsic::x86_sse_cvttss2si64:
if (!Subtarget->hasSSE1())
return false;
IsInputDouble = false;
break;
case Intrinsic::x86_sse2_cvttsd2si:
case Intrinsic::x86_sse2_cvttsd2si64:
if (!Subtarget->hasSSE2())
return false;
IsInputDouble = true;
break;
}
Type *RetTy = I.getCalledFunction()->getReturnType();
MVT VT;
if (!isTypeLegal(RetTy, VT))
return false;
static const unsigned CvtOpc[2][2][2] = {
{ { X86::CVTTSS2SIrr, X86::VCVTTSS2SIrr },
{ X86::CVTTSS2SI64rr, X86::VCVTTSS2SI64rr } },
{ { X86::CVTTSD2SIrr, X86::VCVTTSD2SIrr },
{ X86::CVTTSD2SI64rr, X86::VCVTTSD2SI64rr } }
};
bool HasAVX = Subtarget->hasAVX();
unsigned Opc;
switch (VT.SimpleTy) {
default: llvm_unreachable("Unexpected result type.");
case MVT::i32: Opc = CvtOpc[IsInputDouble][0][HasAVX]; break;
case MVT::i64: Opc = CvtOpc[IsInputDouble][1][HasAVX]; break;
}
// Check if we can fold insertelement instructions into the convert.
const Value *Op = I.getArgOperand(0);
while (auto *IE = dyn_cast<InsertElementInst>(Op)) {
const Value *Index = IE->getOperand(2);
if (!isa<ConstantInt>(Index))
break;
unsigned Idx = cast<ConstantInt>(Index)->getZExtValue();
if (Idx == 0) {
Op = IE->getOperand(1);
break;
}
Op = IE->getOperand(0);
}
unsigned Reg = getRegForValue(Op);
if (Reg == 0)
return false;
unsigned ResultReg = createResultReg(TLI.getRegClassFor(VT));
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), ResultReg)
.addReg(Reg);
UpdateValueMap(&I, ResultReg);
return true;
}
}
}

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@ -0,0 +1,54 @@
; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx,+sse2 -fast-isel -fast-isel-abort | FileCheck %s --check-prefix=SSE
; RUN: llc < %s -mtriple=x86_64-apple-darwin -mattr=-avx2,+avx -fast-isel -fast-isel-abort | FileCheck %s --check-prefix=AVX
define i32 @cvt_test1(float %a) {
; SSE-LABEL: cvt_test1
; SSE: cvttss2si %xmm0, %eax
; AVX-LABEL: cvt_test1
; AVX: vcvttss2si %xmm0, %eax
%1 = insertelement <4 x float> undef, float %a, i32 0
%2 = insertelement <4 x float> %1, float 0.000000e+00, i32 1
%3 = insertelement <4 x float> %2, float 0.000000e+00, i32 2
%4 = insertelement <4 x float> %3, float 0.000000e+00, i32 3
%5 = call i32 @llvm.x86.sse.cvttss2si(<4 x float> %4)
ret i32 %5
}
declare i32 @llvm.x86.sse.cvttss2si(<4 x float>) nounwind readnone
define i64 @cvt_test2(float %a) {
; SSE-LABEL: cvt_test2
; SSE: cvttss2si %xmm0, %rax
; AVX-LABEL: cvt_test2
; AVX: vcvttss2si %xmm0, %rax
%1 = insertelement <4 x float> undef, float %a, i32 0
%2 = insertelement <4 x float> %1, float 0.000000e+00, i32 1
%3 = insertelement <4 x float> %2, float 0.000000e+00, i32 2
%4 = insertelement <4 x float> %3, float 0.000000e+00, i32 3
%5 = call i64 @llvm.x86.sse.cvttss2si64(<4 x float> %4)
ret i64 %5
}
declare i64 @llvm.x86.sse.cvttss2si64(<4 x float>) nounwind readnone
define i32 @cvt_test3(double %a) {
; SSE-LABEL: cvt_test3
; SSE: cvttsd2si %xmm0, %eax
; AVX-LABEL: cvt_test3
; AVX: vcvttsd2si %xmm0, %eax
%1 = insertelement <2 x double> undef, double %a, i32 0
%2 = insertelement <2 x double> %1, double 0.000000e+00, i32 1
%3 = call i32 @llvm.x86.sse2.cvttsd2si(<2 x double> %2)
ret i32 %3
}
declare i32 @llvm.x86.sse2.cvttsd2si(<2 x double>) nounwind readnone
define i64 @cvt_test4(double %a) {
; SSE-LABEL: cvt_test4
; SSE: cvttsd2si %xmm0, %rax
; AVX-LABEL: cvt_test4
; AVX: vcvttsd2si %xmm0, %rax
%1 = insertelement <2 x double> undef, double %a, i32 0
%2 = insertelement <2 x double> %1, double 0.000000e+00, i32 1
%3 = call i64 @llvm.x86.sse2.cvttsd2si64(<2 x double> %2)
ret i64 %3
}
declare i64 @llvm.x86.sse2.cvttsd2si64(<2 x double>) nounwind readnone