[llvm] r345734 - [InstCombine] refactor fabs+fcmp fold; NFC
Sanjay Patel via llvm-commits
llvm-commits at lists.llvm.org
Wed Oct 31 09:34:44 PDT 2018
Author: spatel
Date: Wed Oct 31 09:34:43 2018
New Revision: 345734
URL: http://llvm.org/viewvc/llvm-project?rev=345734&view=rev
Log:
[InstCombine] refactor fabs+fcmp fold; NFC
Also, remove/replace/minimize/enhance the tests for this fold.
The code drops FMF, so it needs more tests and at least 1 fix.
Modified:
llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp
llvm/trunk/test/Transforms/InstCombine/fcmp.ll
Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp?rev=345734&r1=345733&r2=345734&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp Wed Oct 31 09:34:43 2018
@@ -5288,6 +5288,46 @@ static Instruction *foldFCmpReciprocalAn
return NewFCI;
}
+/// Optimize fabs(X) compared with zero.
+static Instruction *foldFabsWithFcmpZero(FCmpInst &I) {
+ Value *X;
+ if (!match(I.getOperand(0), m_Intrinsic<Intrinsic::fabs>(m_Value(X))) ||
+ !match(I.getOperand(1), m_PosZeroFP()))
+ return nullptr;
+
+ switch (I.getPredicate()) {
+ case FCmpInst::FCMP_UGE:
+ case FCmpInst::FCMP_OLT:
+ // fabs(X) >= 0.0 --> true
+ // fabs(X) < 0.0 --> false
+ llvm_unreachable("fcmp should have simplified");
+
+ case FCmpInst::FCMP_OGT:
+ // fabs(X) > 0.0 --> X != 0.0
+ return new FCmpInst(FCmpInst::FCMP_ONE, X, I.getOperand(1));
+
+ case FCmpInst::FCMP_OLE:
+ // fabs(X) <= 0.0 --> X == 0.0
+ return new FCmpInst(FCmpInst::FCMP_OEQ, X, I.getOperand(1));
+
+ case FCmpInst::FCMP_OGE:
+ // fabs(X) >= 0.0 --> !isnan(X)
+ assert(!I.hasNoNaNs() && "fcmp should have simplified");
+ return new FCmpInst(FCmpInst::FCMP_ORD, X, I.getOperand(1));
+
+ case FCmpInst::FCMP_OEQ:
+ case FCmpInst::FCMP_UEQ:
+ case FCmpInst::FCMP_ONE:
+ case FCmpInst::FCMP_UNE:
+ // fabs(X) == 0.0 --> X == 0.0
+ // fabs(X) != 0.0 --> X != 0.0
+ return new FCmpInst(I.getPredicate(), X, I.getOperand(1));
+
+ default:
+ return nullptr;
+ }
+}
+
Instruction *InstCombiner::visitFCmpInst(FCmpInst &I) {
bool Changed = false;
@@ -5418,45 +5458,11 @@ Instruction *InstCombiner::visitFCmpInst
if (Instruction *Res = foldCmpLoadFromIndexedGlobal(GEP, GV, I))
return Res;
break;
- case Instruction::Call: {
- if (!RHSC->isNullValue())
- break;
-
- CallInst *CI = cast<CallInst>(LHSI);
- Intrinsic::ID IID = getIntrinsicForCallSite(CI, &TLI);
- if (IID != Intrinsic::fabs)
- break;
-
- // Various optimization for fabs compared with zero.
- switch (Pred) {
- default:
- break;
- case FCmpInst::FCMP_UGE:
- case FCmpInst::FCMP_OLT:
- // fabs(x) >= 0.0 --> true
- // fabs(x) < 0.0 --> false
- llvm_unreachable("fcmp should have simplified");
-
- // fabs(x) > 0 --> x != 0
- case FCmpInst::FCMP_OGT:
- return new FCmpInst(FCmpInst::FCMP_ONE, CI->getArgOperand(0), RHSC);
- // fabs(x) <= 0 --> x == 0
- case FCmpInst::FCMP_OLE:
- return new FCmpInst(FCmpInst::FCMP_OEQ, CI->getArgOperand(0), RHSC);
- // fabs(x) >= 0 --> !isnan(x)
- case FCmpInst::FCMP_OGE:
- assert(!I.hasNoNaNs() && "fcmp should have simplified");
- return new FCmpInst(FCmpInst::FCMP_ORD, CI->getArgOperand(0), RHSC);
- // fabs(x) == 0 --> x == 0
- // fabs(x) != 0 --> x != 0
- case FCmpInst::FCMP_OEQ:
- case FCmpInst::FCMP_UEQ:
- case FCmpInst::FCMP_ONE:
- case FCmpInst::FCMP_UNE:
- return new FCmpInst(Pred, CI->getArgOperand(0), RHSC);
- }
- }
- }
+ case Instruction::Call:
+ if (Instruction *X = foldFabsWithFcmpZero(I))
+ return X;
+ break;
+ }
}
// fcmp pred (fneg x), (fneg y) -> fcmp swap(pred) x, y
Modified: llvm/trunk/test/Transforms/InstCombine/fcmp.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/fcmp.ll?rev=345734&r1=345733&r2=345734&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/fcmp.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/fcmp.ll Wed Oct 31 09:34:43 2018
@@ -1,7 +1,9 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -instcombine < %s | FileCheck %s
-declare double @llvm.fabs.f64(double) readnone
+declare half @llvm.fabs.f16(half)
+declare double @llvm.fabs.f64(double)
+declare <2 x float> @llvm.fabs.v2f32(<2 x float>)
define i1 @test1(float %x, float %y) {
; CHECK-LABEL: @test1(
@@ -133,194 +135,92 @@ define float @test8(float %x) {
; Float comparison to zero shouldn't cast to double.
}
-declare double @fabs(double) readnone
-
-define i32 @test9(double %a) {
-; CHECK-LABEL: @test9(
-; CHECK-NEXT: ret i32 0
-;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp olt double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test9_intrinsic(double %a) {
-; CHECK-LABEL: @test9_intrinsic(
-; CHECK-NEXT: ret i32 0
-;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp olt double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test10(double %a) {
-; CHECK-LABEL: @test10(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp oeq double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+define i1 @fabs_uge(double %a) {
+; CHECK-LABEL: @fabs_uge(
+; CHECK-NEXT: ret i1 true
;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp ole double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call double @llvm.fabs.f64(double %a)
+ %cmp = fcmp uge double %call, 0.0
+ ret i1 %cmp
}
-define i32 @test10_intrinsic(double %a) {
-; CHECK-LABEL: @test10_intrinsic(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp oeq double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+define i1 @fabs_olt(half %a) {
+; CHECK-LABEL: @fabs_olt(
+; CHECK-NEXT: ret i1 false
;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp ole double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call half @llvm.fabs.f16(half %a)
+ %cmp = fcmp olt half %call, 0.0
+ ret i1 %cmp
}
-define i32 @test11(double %a) {
-; CHECK-LABEL: @test11(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp one double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+define <2 x i1> @fabs_ole(<2 x float> %a) {
+; CHECK-LABEL: @fabs_ole(
+; CHECK-NEXT: [[CMP:%.*]] = fcmp oeq <2 x float> [[A:%.*]], zeroinitializer
+; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp ogt double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call <2 x float> @llvm.fabs.v2f32(<2 x float> %a)
+ %cmp = fcmp ole <2 x float> %call, zeroinitializer
+ ret <2 x i1> %cmp
}
-define i32 @test11_intrinsic(double %a) {
-; CHECK-LABEL: @test11_intrinsic(
+define i1 @fabs_ogt(double %a) {
+; CHECK-LABEL: @fabs_ogt(
; CHECK-NEXT: [[CMP:%.*]] = fcmp one double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
-;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp ogt double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test12(double %a) {
-; CHECK-LABEL: @test12(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp ord double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+; CHECK-NEXT: ret i1 [[CMP]]
;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp oge double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call double @llvm.fabs.f64(double %a)
+ %cmp = fcmp ogt double %call, 0.0
+ ret i1 %cmp
}
-define i32 @test12_intrinsic(double %a) {
-; CHECK-LABEL: @test12_intrinsic(
+define i1 @fabs_oge(double %a) {
+; CHECK-LABEL: @fabs_oge(
; CHECK-NEXT: [[CMP:%.*]] = fcmp ord double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
-;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp oge double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test13(double %a) {
-; CHECK-LABEL: @test13(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp une double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
-;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp une double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test13_intrinsic(double %a) {
-; CHECK-LABEL: @test13_intrinsic(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp une double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+; CHECK-NEXT: ret i1 [[CMP]]
;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp une double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call double @llvm.fabs.f64(double %a)
+ %cmp = fcmp oge double %call, 0.0
+ ret i1 %cmp
}
-define i32 @test14(double %a) {
-; CHECK-LABEL: @test14(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp oeq double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+define i1 @fabs_une(half %a) {
+; CHECK-LABEL: @fabs_une(
+; CHECK-NEXT: [[CMP:%.*]] = fcmp une half [[A:%.*]], 0xH0000
+; CHECK-NEXT: ret i1 [[CMP]]
;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp oeq double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call half @llvm.fabs.f16(half %a)
+ %cmp = fcmp une half %call, 0.0
+ ret i1 %cmp
}
-define i32 @test14_intrinsic(double %a) {
-; CHECK-LABEL: @test14_intrinsic(
+define i1 @fabs_oeq(double %a) {
+; CHECK-LABEL: @fabs_oeq(
; CHECK-NEXT: [[CMP:%.*]] = fcmp oeq double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+; CHECK-NEXT: ret i1 [[CMP]]
;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp oeq double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call double @llvm.fabs.f64(double %a)
+ %cmp = fcmp oeq double %call, 0.0
+ ret i1 %cmp
}
-define i32 @test15(double %a) {
-; CHECK-LABEL: @test15(
+define i1 @fabs_one(double %a) {
+; CHECK-LABEL: @fabs_one(
; CHECK-NEXT: [[CMP:%.*]] = fcmp one double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+; CHECK-NEXT: ret i1 [[CMP]]
;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp one double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call double @llvm.fabs.f64(double %a)
+ %cmp = fcmp one double %call, 0.0
+ ret i1 %cmp
}
-define i32 @test15_intrinsic(double %a) {
-; CHECK-LABEL: @test15_intrinsic(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp one double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
+define <2 x i1> @fabs_ueq(<2 x float> %a) {
+; CHECK-LABEL: @fabs_ueq(
+; CHECK-NEXT: [[CMP:%.*]] = fcmp ueq <2 x float> [[A:%.*]], zeroinitializer
+; CHECK-NEXT: ret <2 x i1> [[CMP]]
;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp one double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test16(double %a) {
-; CHECK-LABEL: @test16(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp ueq double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
-;
- %call = tail call double @fabs(double %a)
- %cmp = fcmp ueq double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
-}
-
-define i32 @test16_intrinsic(double %a) {
-; CHECK-LABEL: @test16_intrinsic(
-; CHECK-NEXT: [[CMP:%.*]] = fcmp ueq double [[A:%.*]], 0.000000e+00
-; CHECK-NEXT: [[CONV:%.*]] = zext i1 [[CMP]] to i32
-; CHECK-NEXT: ret i32 [[CONV]]
-;
- %call = tail call double @llvm.fabs.f64(double %a)
- %cmp = fcmp ueq double %call, 0.000000e+00
- %conv = zext i1 %cmp to i32
- ret i32 %conv
+ %call = call <2 x float> @llvm.fabs.v2f32(<2 x float> %a)
+ %cmp = fcmp ueq <2 x float> %call, zeroinitializer
+ ret <2 x i1> %cmp
}
; Don't crash.
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