[clang] [InstSimplify] Simplify `icmp X & C1, X & C2` when `(C1 & C2) == C1/C2` (PR #65905)
Yingwei Zheng via cfe-commits
cfe-commits at lists.llvm.org
Sun Sep 17 05:43:06 PDT 2023
https://github.com/dtcxzyw updated https://github.com/llvm/llvm-project/pull/65905
>From f178af6d47ce6d982c6568ba6e0db517de124291 Mon Sep 17 00:00:00 2001
From: Yingwei Zheng <dtcxzyw2333 at gmail.com>
Date: Mon, 11 Sep 2023 02:01:12 +0800
Subject: [PATCH] [InstSimplify] Simplify `icmp X & C1, X & C2` when `(C1 & C2)
== C1/C2`
---
llvm/lib/Analysis/InstructionSimplify.cpp | 28 ++-
llvm/test/Transforms/InstSimplify/compare.ll | 194 ++++++++++++++++++
.../InstSimplify/maxmin_intrinsics.ll | 97 +++++++++
3 files changed, 318 insertions(+), 1 deletion(-)
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index d0cc56ebc2be319..734029f1ad0bef5 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -3427,7 +3427,7 @@ static Value *simplifyICmpWithBinOp(CmpInst::Predicate Pred, Value *LHS,
switch (LBO->getOpcode()) {
default:
break;
- case Instruction::Shl:
+ case Instruction::Shl: {
bool NUW = Q.IIQ.hasNoUnsignedWrap(LBO) && Q.IIQ.hasNoUnsignedWrap(RBO);
bool NSW = Q.IIQ.hasNoSignedWrap(LBO) && Q.IIQ.hasNoSignedWrap(RBO);
if (!NUW || (ICmpInst::isSigned(Pred) && !NSW) ||
@@ -3436,6 +3436,32 @@ static Value *simplifyICmpWithBinOp(CmpInst::Predicate Pred, Value *LHS,
if (Value *V = simplifyICmpInst(Pred, LBO->getOperand(1),
RBO->getOperand(1), Q, MaxRecurse - 1))
return V;
+ break;
+ }
+ // icmp X & C1, X & C2 where (C1 & C2) == C1/C2
+ // icmp X | C1, X | C2 where (C1 & C2) == C1/C2
+ case Instruction::And:
+ case Instruction::Or: {
+ if (ICmpInst::isUnsigned(Pred)) {
+ const APInt *C1, *C2;
+ if (match(LBO->getOperand(1), m_APInt(C1)) &&
+ match(RBO->getOperand(1), m_APInt(C2))) {
+ if (C1->isSubsetOf(*C2)) {
+ if (Pred == ICmpInst::ICMP_ULE)
+ return ConstantInt::getTrue(getCompareTy(LHS));
+ if (Pred == ICmpInst::ICMP_UGT)
+ return ConstantInt::getFalse(getCompareTy(LHS));
+ }
+ if (C2->isSubsetOf(*C1)) {
+ if (Pred == ICmpInst::ICMP_UGE)
+ return ConstantInt::getTrue(getCompareTy(LHS));
+ if (Pred == ICmpInst::ICMP_ULT)
+ return ConstantInt::getFalse(getCompareTy(LHS));
+ }
+ }
+ }
+ break;
+ }
}
}
diff --git a/llvm/test/Transforms/InstSimplify/compare.ll b/llvm/test/Transforms/InstSimplify/compare.ll
index c6c104a41c8be70..d21af97494c88bc 100644
--- a/llvm/test/Transforms/InstSimplify/compare.ll
+++ b/llvm/test/Transforms/InstSimplify/compare.ll
@@ -1919,6 +1919,200 @@ define i1 @tautological8(i32 %A, i32 %B) {
ret i1 %D
}
+define i1 @tautological9(i32 %A) {
+; CHECK-LABEL: @tautological9(
+; CHECK-NEXT: ret i1 false
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 3
+ %D = icmp ugt i32 %C1, %C2
+ ret i1 %D
+}
+
+define <2 x i1> @tautological9_vec(<2 x i32> %A) {
+; CHECK-LABEL: @tautological9_vec(
+; CHECK-NEXT: ret <2 x i1> zeroinitializer
+;
+ %C1 = and <2 x i32> %A, <i32 1, i32 1>
+ %C2 = and <2 x i32> %A, <i32 3, i32 3>
+ %D = icmp ugt <2 x i32> %C1, %C2
+ ret <2 x i1> %D
+}
+
+define i1 @tautological10(i32 %A) {
+; CHECK-LABEL: @tautological10(
+; CHECK-NEXT: ret i1 true
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 3
+ %D = icmp ule i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological11(i32 %A) {
+; CHECK-LABEL: @tautological11(
+; CHECK-NEXT: ret i1 true
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 3
+ %D = icmp ule i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological12(i32 %A) {
+; CHECK-LABEL: @tautological12(
+; CHECK-NEXT: ret i1 false
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 3
+ %D = icmp ugt i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological13(i32 %A) {
+; CHECK-LABEL: @tautological13(
+; CHECK-NEXT: ret i1 false
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 3
+ %D = icmp ult i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological14(i32 %A) {
+; CHECK-LABEL: @tautological14(
+; CHECK-NEXT: ret i1 true
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 3
+ %D = icmp uge i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological15(i32 %A) {
+; CHECK-LABEL: @tautological15(
+; CHECK-NEXT: ret i1 true
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 3
+ %D = icmp uge i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological16(i32 %A) {
+; CHECK-LABEL: @tautological16(
+; CHECK-NEXT: ret i1 false
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 3
+ %D = icmp ult i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological9_negative(i32 %A) {
+; CHECK-LABEL: @tautological9_negative(
+; CHECK-NEXT: [[C1:%.*]] = and i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = and i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp ugt i32 [[C1]], [[C2]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 2
+ %D = icmp ugt i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological10_negative(i32 %A) {
+; CHECK-LABEL: @tautological10_negative(
+; CHECK-NEXT: [[C1:%.*]] = and i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = and i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp ule i32 [[C1]], [[C2]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 2
+ %D = icmp ule i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological11_negative(i32 %A) {
+; CHECK-LABEL: @tautological11_negative(
+; CHECK-NEXT: [[C1:%.*]] = or i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = or i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp ule i32 [[C1]], [[C2]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 2
+ %D = icmp ule i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological12_negative(i32 %A) {
+; CHECK-LABEL: @tautological12_negative(
+; CHECK-NEXT: [[C1:%.*]] = or i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = or i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp ugt i32 [[C1]], [[C2]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 2
+ %D = icmp ugt i32 %C1, %C2
+ ret i1 %D
+}
+
+define i1 @tautological13_negative(i32 %A) {
+; CHECK-LABEL: @tautological13_negative(
+; CHECK-NEXT: [[C1:%.*]] = or i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = or i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp ult i32 [[C2]], [[C1]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 2
+ %D = icmp ult i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological14_negative(i32 %A) {
+; CHECK-LABEL: @tautological14_negative(
+; CHECK-NEXT: [[C1:%.*]] = or i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = or i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp uge i32 [[C2]], [[C1]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = or i32 %A, 1
+ %C2 = or i32 %A, 2
+ %D = icmp uge i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological15_negative(i32 %A) {
+; CHECK-LABEL: @tautological15_negative(
+; CHECK-NEXT: [[C1:%.*]] = and i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = and i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp uge i32 [[C2]], [[C1]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 2
+ %D = icmp uge i32 %C2, %C1
+ ret i1 %D
+}
+
+define i1 @tautological16_negative(i32 %A) {
+; CHECK-LABEL: @tautological16_negative(
+; CHECK-NEXT: [[C1:%.*]] = and i32 [[A:%.*]], 1
+; CHECK-NEXT: [[C2:%.*]] = and i32 [[A]], 2
+; CHECK-NEXT: [[D:%.*]] = icmp ult i32 [[C2]], [[C1]]
+; CHECK-NEXT: ret i1 [[D]]
+;
+ %C1 = and i32 %A, 1
+ %C2 = and i32 %A, 2
+ %D = icmp ult i32 %C2, %C1
+ ret i1 %D
+}
+
declare void @helper_i1(i1)
; Series of tests for icmp s[lt|ge] (or A, B), A and icmp s[gt|le] A, (or A, B)
define void @icmp_slt_sge_or(i32 %Ax, i32 %Bx) {
diff --git a/llvm/test/Transforms/InstSimplify/maxmin_intrinsics.ll b/llvm/test/Transforms/InstSimplify/maxmin_intrinsics.ll
index e7123b208084927..8828378b5315df0 100644
--- a/llvm/test/Transforms/InstSimplify/maxmin_intrinsics.ll
+++ b/llvm/test/Transforms/InstSimplify/maxmin_intrinsics.ll
@@ -2332,3 +2332,100 @@ false:
%m2 = call i8 @llvm.smin.i8(i8 %x, i8 %y)
ret i8 %m2
}
+
+; Tests from PR65833
+define i8 @umin_and_mask(i8 %x) {
+; CHECK-LABEL: @umin_and_mask(
+; CHECK-NEXT: [[AND1:%.*]] = and i8 [[X:%.*]], 1
+; CHECK-NEXT: ret i8 [[AND1]]
+;
+ %and1 = and i8 %x, 1
+ %and2 = and i8 %x, 3
+ %val = call i8 @llvm.umin.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umax_and_mask(i8 %x) {
+; CHECK-LABEL: @umax_and_mask(
+; CHECK-NEXT: [[AND2:%.*]] = and i8 [[X:%.*]], 3
+; CHECK-NEXT: ret i8 [[AND2]]
+;
+ %and1 = and i8 %x, 1
+ %and2 = and i8 %x, 3
+ %val = call i8 @llvm.umax.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umin_or_mask(i8 %x) {
+; CHECK-LABEL: @umin_or_mask(
+; CHECK-NEXT: [[AND1:%.*]] = or i8 [[X:%.*]], 1
+; CHECK-NEXT: ret i8 [[AND1]]
+;
+ %and1 = or i8 %x, 1
+ %and2 = or i8 %x, 3
+ %val = call i8 @llvm.umin.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umax_or_mask(i8 %x) {
+; CHECK-LABEL: @umax_or_mask(
+; CHECK-NEXT: [[AND2:%.*]] = or i8 [[X:%.*]], 3
+; CHECK-NEXT: ret i8 [[AND2]]
+;
+ %and1 = or i8 %x, 1
+ %and2 = or i8 %x, 3
+ %val = call i8 @llvm.umax.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umin_and_mask_negative(i8 %x) {
+; CHECK-LABEL: @umin_and_mask_negative(
+; CHECK-NEXT: [[AND1:%.*]] = and i8 [[X:%.*]], 1
+; CHECK-NEXT: [[AND2:%.*]] = and i8 [[X]], 2
+; CHECK-NEXT: [[VAL:%.*]] = call i8 @llvm.umin.i8(i8 [[AND1]], i8 [[AND2]])
+; CHECK-NEXT: ret i8 [[VAL]]
+;
+ %and1 = and i8 %x, 1
+ %and2 = and i8 %x, 2
+ %val = call i8 @llvm.umin.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umax_and_mask_negative(i8 %x) {
+; CHECK-LABEL: @umax_and_mask_negative(
+; CHECK-NEXT: [[AND1:%.*]] = and i8 [[X:%.*]], 1
+; CHECK-NEXT: [[AND2:%.*]] = and i8 [[X]], 2
+; CHECK-NEXT: [[VAL:%.*]] = call i8 @llvm.umax.i8(i8 [[AND1]], i8 [[AND2]])
+; CHECK-NEXT: ret i8 [[VAL]]
+;
+ %and1 = and i8 %x, 1
+ %and2 = and i8 %x, 2
+ %val = call i8 @llvm.umax.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umin_or_mask_negative(i8 %x) {
+; CHECK-LABEL: @umin_or_mask_negative(
+; CHECK-NEXT: [[AND1:%.*]] = or i8 [[X:%.*]], 1
+; CHECK-NEXT: [[AND2:%.*]] = or i8 [[X]], 2
+; CHECK-NEXT: [[VAL:%.*]] = call i8 @llvm.umin.i8(i8 [[AND1]], i8 [[AND2]])
+; CHECK-NEXT: ret i8 [[VAL]]
+;
+ %and1 = or i8 %x, 1
+ %and2 = or i8 %x, 2
+ %val = call i8 @llvm.umin.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
+
+define i8 @umax_or_mask_negative(i8 %x) {
+; CHECK-LABEL: @umax_or_mask_negative(
+; CHECK-NEXT: [[AND1:%.*]] = or i8 [[X:%.*]], 1
+; CHECK-NEXT: [[AND2:%.*]] = or i8 [[X]], 2
+; CHECK-NEXT: [[VAL:%.*]] = call i8 @llvm.umax.i8(i8 [[AND1]], i8 [[AND2]])
+; CHECK-NEXT: ret i8 [[VAL]]
+;
+ %and1 = or i8 %x, 1
+ %and2 = or i8 %x, 2
+ %val = call i8 @llvm.umax.i8(i8 %and1, i8 %and2)
+ ret i8 %val
+}
More information about the cfe-commits
mailing list