[clang-tools-extra] [InstCombine] Simplify the pattern `a ne/eq (zext (a ne/eq c))` (PR #65852)
Yingwei Zheng via cfe-commits
cfe-commits at lists.llvm.org
Mon Sep 18 07:33:03 PDT 2023
https://github.com/dtcxzyw updated https://github.com/llvm/llvm-project/pull/65852
>From d9d8bcbb98e8f5aecb9733329389d61a489bd731 Mon Sep 17 00:00:00 2001
From: Yingwei Zheng <dtcxzyw2333 at gmail.com>
Date: Sat, 9 Sep 2023 23:07:29 +0800
Subject: [PATCH] [InstCombine] Simplify the pattern `a ne/eq (zext (a ne/eq
c))`
---
.../InstCombine/InstCombineCompares.cpp | 62 ++++++
.../test/Transforms/InstCombine/icmp-range.ll | 181 ++++++++++++++++++
2 files changed, 243 insertions(+)
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 9fdc46fec631679..837b8e6d2619989 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -6309,7 +6309,69 @@ Instruction *InstCombinerImpl::foldICmpUsingBoolRange(ICmpInst &I) {
Y->getType()->isIntOrIntVectorTy(1) && Pred == ICmpInst::ICMP_ULE)
return BinaryOperator::CreateOr(Builder.CreateIsNull(X), Y);
+ ICmpInst::Predicate Pred1, Pred2;
const APInt *C;
+ // icmp eq/ne X, (zext (icmp eq/ne X, C))
+ if (match(&I, m_c_ICmp(Pred1, m_Value(X),
+ m_ZExt(m_ICmp(Pred2, m_Deferred(X), m_APInt(C))))) &&
+ ICmpInst::isEquality(Pred1) && ICmpInst::isEquality(Pred2)) {
+ if (C->isZero()) {
+ if (Pred2 == ICmpInst::ICMP_EQ) {
+ // icmp eq X, (zext (icmp eq X, 0)) --> false
+ // icmp ne X, (zext (icmp eq X, 0)) --> true
+ return replaceInstUsesWith(
+ I,
+ Constant::getIntegerValue(
+ I.getType(),
+ APInt(1U, static_cast<uint64_t>(Pred1 == ICmpInst::ICMP_NE))));
+ } else {
+ // icmp eq X, (zext (icmp ne X, 0)) --> icmp ult X, 2
+ // icmp ne X, (zext (icmp ne X, 0)) --> icmp ugt X, 1
+ return ICmpInst::Create(
+ Instruction::ICmp,
+ Pred1 == ICmpInst::ICMP_NE ? ICmpInst::ICMP_UGT
+ : ICmpInst::ICMP_ULT,
+ X,
+ Constant::getIntegerValue(
+ X->getType(), APInt(X->getType()->getScalarSizeInBits(),
+ Pred1 == ICmpInst::ICMP_NE ? 1 : 2)));
+ }
+ } else if (C->isOne()) {
+ if (Pred2 == ICmpInst::ICMP_NE) {
+ // icmp eq X, (zext (icmp ne X, 1)) --> false
+ // icmp ne X, (zext (icmp ne X, 1)) --> true
+ return replaceInstUsesWith(
+ I,
+ Constant::getIntegerValue(
+ I.getType(),
+ APInt(1U, static_cast<uint64_t>(Pred1 == ICmpInst::ICMP_NE))));
+ } else {
+ // icmp eq X, (zext (icmp eq X, 1)) --> icmp ult X, 2
+ // icmp ne X, (zext (icmp eq X, 1)) --> icmp ugt X, 1
+ return ICmpInst::Create(
+ Instruction::ICmp,
+ Pred1 == ICmpInst::ICMP_NE ? ICmpInst::ICMP_UGT
+ : ICmpInst::ICMP_ULT,
+ X,
+ Constant::getIntegerValue(
+ X->getType(), APInt(X->getType()->getScalarSizeInBits(),
+ Pred1 == ICmpInst::ICMP_NE ? 1 : 2)));
+ }
+ } else {
+ // C != 0 && C != 1
+ // icmp eq X, (zext (icmp eq X, C)) --> icmp eq X, 0
+ // icmp eq X, (zext (icmp ne X, C)) --> icmp eq X, 1
+ // icmp ne X, (zext (icmp eq X, C)) --> icmp ne X, 0
+ // icmp ne X, (zext (icmp ne X, C)) --> icmp ne X, 1
+ return ICmpInst::Create(
+ Instruction::ICmp, Pred1, X,
+ Constant::getIntegerValue(
+ X->getType(),
+ APInt(X->getType()->getScalarSizeInBits(),
+ static_cast<uint64_t>(Pred2 == ICmpInst::ICMP_NE))));
+ }
+ }
+
if (match(I.getOperand(0), m_c_Add(m_ZExt(m_Value(X)), m_SExt(m_Value(Y)))) &&
match(I.getOperand(1), m_APInt(C)) &&
X->getType()->isIntOrIntVectorTy(1) &&
diff --git a/llvm/test/Transforms/InstCombine/icmp-range.ll b/llvm/test/Transforms/InstCombine/icmp-range.ll
index 4281e09cb0309c8..15424fce33fdeea 100644
--- a/llvm/test/Transforms/InstCombine/icmp-range.ll
+++ b/llvm/test/Transforms/InstCombine/icmp-range.ll
@@ -1034,6 +1034,187 @@ define i1 @icmp_ne_bool_1(ptr %ptr) {
ret i1 %cmp
}
+define i1 @icmp_ne_zext_eq_zero(i32 %a) {
+; CHECK-LABEL: @icmp_ne_zext_eq_zero(
+; CHECK-NEXT: ret i1 true
+;
+ %cmp = icmp eq i32 %a, 0
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp ne i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_ne_zext_ne_zero(i32 %a) {
+; CHECK-LABEL: @icmp_ne_zext_ne_zero(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i32 [[A:%.*]], 1
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp ne i32 %a, 0
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp ne i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_eq_zext_eq_zero(i32 %a) {
+; CHECK-LABEL: @icmp_eq_zext_eq_zero(
+; CHECK-NEXT: ret i1 false
+;
+ %cmp = icmp eq i32 %a, 0
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp eq i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_eq_zext_ne_zero(i32 %a) {
+; CHECK-LABEL: @icmp_eq_zext_ne_zero(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i32 [[A:%.*]], 2
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp ne i32 %a, 0
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp eq i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_ne_zext_eq_one(i32 %a) {
+; CHECK-LABEL: @icmp_ne_zext_eq_one(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i32 [[A:%.*]], 1
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp eq i32 %a, 1
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp ne i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_ne_zext_ne_one(i32 %a) {
+; CHECK-LABEL: @icmp_ne_zext_ne_one(
+; CHECK-NEXT: ret i1 true
+;
+ %cmp = icmp ne i32 %a, 1
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp ne i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_eq_zext_eq_one(i32 %a) {
+; CHECK-LABEL: @icmp_eq_zext_eq_one(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i32 [[A:%.*]], 2
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp eq i32 %a, 1
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp eq i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_eq_zext_ne_one(i32 %a) {
+; CHECK-LABEL: @icmp_eq_zext_ne_one(
+; CHECK-NEXT: ret i1 false
+;
+ %cmp = icmp ne i32 %a, 1
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp eq i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_ne_zext_eq_non_boolean(i32 %a) {
+; CHECK-LABEL: @icmp_ne_zext_eq_non_boolean(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i32 [[A:%.*]], 0
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp eq i32 %a, 2
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp ne i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_ne_zext_ne_non_boolean(i32 %a) {
+; CHECK-LABEL: @icmp_ne_zext_ne_non_boolean(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i32 [[A:%.*]], 1
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp ne i32 %a, 2
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp ne i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_eq_zext_eq_non_boolean(i32 %a) {
+; CHECK-LABEL: @icmp_eq_zext_eq_non_boolean(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[A:%.*]], 0
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp eq i32 %a, 2
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp eq i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define i1 @icmp_eq_zext_ne_non_boolean(i32 %a) {
+; CHECK-LABEL: @icmp_eq_zext_ne_non_boolean(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[A:%.*]], 1
+; CHECK-NEXT: ret i1 [[CMP1]]
+;
+ %cmp = icmp ne i32 %a, 2
+ %conv = zext i1 %cmp to i32
+ %cmp1 = icmp eq i32 %conv, %a
+ ret i1 %cmp1
+}
+
+define <2 x i1> @icmp_ne_zext_eq_zero_vec(<2 x i32> %a) {
+; CHECK-LABEL: @icmp_ne_zext_eq_zero_vec(
+; CHECK-NEXT: ret <2 x i1> <i1 true, i1 true>
+;
+ %cmp = icmp eq <2 x i32> %a, <i32 0, i32 0>
+ %conv = zext <2 x i1> %cmp to <2 x i32>
+ %cmp1 = icmp ne <2 x i32> %conv, %a
+ ret <2 x i1> %cmp1
+}
+
+define <2 x i1> @icmp_ne_zext_ne_zero_vec(<2 x i32> %a) {
+; CHECK-LABEL: @icmp_ne_zext_ne_zero_vec(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt <2 x i32> [[A:%.*]], <i32 1, i32 1>
+; CHECK-NEXT: ret <2 x i1> [[CMP1]]
+;
+ %cmp = icmp ne <2 x i32> %a, <i32 0, i32 0>
+ %conv = zext <2 x i1> %cmp to <2 x i32>
+ %cmp1 = icmp ne <2 x i32> %conv, %a
+ ret <2 x i1> %cmp1
+}
+
+define <2 x i1> @icmp_ne_zext_eq_one_vec(<2 x i32> %a) {
+; CHECK-LABEL: @icmp_ne_zext_eq_one_vec(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt <2 x i32> [[A:%.*]], <i32 1, i32 1>
+; CHECK-NEXT: ret <2 x i1> [[CMP1]]
+;
+ %cmp = icmp eq <2 x i32> %a, <i32 1, i32 1>
+ %conv = zext <2 x i1> %cmp to <2 x i32>
+ %cmp1 = icmp ne <2 x i32> %conv, %a
+ ret <2 x i1> %cmp1
+}
+
+define <2 x i1> @icmp_ne_zext_ne_one_vec(<2 x i32> %a) {
+; CHECK-LABEL: @icmp_ne_zext_ne_one_vec(
+; CHECK-NEXT: ret <2 x i1> <i1 true, i1 true>
+;
+ %cmp = icmp ne <2 x i32> %a, <i32 1, i32 1>
+ %conv = zext <2 x i1> %cmp to <2 x i32>
+ %cmp1 = icmp ne <2 x i32> %conv, %a
+ ret <2 x i1> %cmp1
+}
+
+define <2 x i1> @icmp_ne_zext_eq_non_boolean_vec(<2 x i32> %a) {
+; CHECK-LABEL: @icmp_ne_zext_eq_non_boolean_vec(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ne <2 x i32> [[A:%.*]], zeroinitializer
+; CHECK-NEXT: ret <2 x i1> [[CMP1]]
+;
+ %cmp = icmp eq <2 x i32> %a, <i32 2, i32 2>
+ %conv = zext <2 x i1> %cmp to <2 x i32>
+ %cmp1 = icmp ne <2 x i32> %conv, %a
+ ret <2 x i1> %cmp1
+}
+
!0 = !{i32 1, i32 6}
!1 = !{i32 0, i32 6}
!2 = !{i8 0, i8 1}
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