From 447a4485c56641b57f762d87dc2f11da8801d75c Mon Sep 17 00:00:00 2001 From: Hirochika Matsumoto Date: Thu, 31 Mar 2022 03:53:11 +0900 Subject: [PATCH] [InstSimplify] Fold (ctpop(X) == N) || (X != 0) into X != 0 where N > 0 (ctpop(X) == N) || (X != 0) --> (X != 0) https://alive2.llvm.org/ce/z/udgUVV (ctpop(X) != N) && (X == 0) --> (X == 0) https://alive2.llvm.org/ce/z/9dq-cR Differential Revision: https://reviews.llvm.org/D122757 --- llvm/lib/Analysis/InstructionSimplify.cpp | 31 +++++++++++++++++++ .../InstSimplify/and-or-icmp-ctpop.ll | 28 +++++------------ 2 files changed, 39 insertions(+), 20 deletions(-) diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index 77d600ac5883..80fe656367fa 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -1803,6 +1803,27 @@ static Value *simplifyAndOrOfICmpsWithLimitConst(ICmpInst *Cmp0, ICmpInst *Cmp1, return nullptr; } +/// Try to simplify and/or of icmp with ctpop intrinsic. +static Value *simplifyAndOrOfICmpsWithCtpop(ICmpInst *Cmp0, ICmpInst *Cmp1, + bool IsAnd) { + ICmpInst::Predicate Pred0, Pred1; + Value *X; + const APInt *C; + if (!match(Cmp0, m_ICmp(Pred0, m_Intrinsic(m_Value(X)), + m_APInt(C))) || + !match(Cmp1, m_ICmp(Pred1, m_Specific(X), m_ZeroInt())) || C->isZero()) + return nullptr; + + // (ctpop(X) == C) || (X != 0) --> X != 0 where C > 0 + if (!IsAnd && Pred0 == ICmpInst::ICMP_EQ && Pred1 == ICmpInst::ICMP_NE) + return Cmp1; + // (ctpop(X) != C) && (X == 0) --> X == 0 where C > 0 + if (IsAnd && Pred0 == ICmpInst::ICMP_NE && Pred1 == ICmpInst::ICMP_EQ) + return Cmp1; + + return nullptr; +} + static Value *simplifyAndOfICmps(ICmpInst *Op0, ICmpInst *Op1, const SimplifyQuery &Q) { if (Value *X = simplifyUnsignedRangeCheck(Op0, Op1, /*IsAnd=*/true, Q)) @@ -1824,6 +1845,11 @@ static Value *simplifyAndOfICmps(ICmpInst *Op0, ICmpInst *Op1, if (Value *X = simplifyAndOrOfICmpsWithZero(Op0, Op1, true)) return X; + if (Value *X = simplifyAndOrOfICmpsWithCtpop(Op0, Op1, true)) + return X; + if (Value *X = simplifyAndOrOfICmpsWithCtpop(Op1, Op0, true)) + return X; + if (Value *X = simplifyAndOfICmpsWithAdd(Op0, Op1, Q.IIQ)) return X; if (Value *X = simplifyAndOfICmpsWithAdd(Op1, Op0, Q.IIQ)) @@ -1900,6 +1926,11 @@ static Value *simplifyOrOfICmps(ICmpInst *Op0, ICmpInst *Op1, if (Value *X = simplifyAndOrOfICmpsWithZero(Op0, Op1, false)) return X; + if (Value *X = simplifyAndOrOfICmpsWithCtpop(Op0, Op1, false)) + return X; + if (Value *X = simplifyAndOrOfICmpsWithCtpop(Op1, Op0, false)) + return X; + if (Value *X = simplifyOrOfICmpsWithAdd(Op0, Op1, Q.IIQ)) return X; if (Value *X = simplifyOrOfICmpsWithAdd(Op1, Op0, Q.IIQ)) diff --git a/llvm/test/Transforms/InstSimplify/and-or-icmp-ctpop.ll b/llvm/test/Transforms/InstSimplify/and-or-icmp-ctpop.ll index c65adb95a40d..6de97c3a7a76 100644 --- a/llvm/test/Transforms/InstSimplify/and-or-icmp-ctpop.ll +++ b/llvm/test/Transforms/InstSimplify/and-or-icmp-ctpop.ll @@ -12,11 +12,8 @@ declare i32 @llvm.ctpop.i32(i32) define i1 @eq_or_non_0(i32 %x) { ; CHECK-LABEL: @eq_or_non_0( -; CHECK-NEXT: [[T0:%.*]] = tail call i32 @llvm.ctpop.i32(i32 [[X:%.*]]) -; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[T0]], 10 -; CHECK-NEXT: [[NOTZERO:%.*]] = icmp ne i32 [[X]], 0 -; CHECK-NEXT: [[R:%.*]] = or i1 [[NOTZERO]], [[CMP]] -; CHECK-NEXT: ret i1 [[R]] +; CHECK-NEXT: [[NOTZERO:%.*]] = icmp ne i32 [[X:%.*]], 0 +; CHECK-NEXT: ret i1 [[NOTZERO]] ; %t0 = tail call i32 @llvm.ctpop.i32(i32 %x) %cmp = icmp eq i32 %t0, 10 @@ -29,11 +26,8 @@ declare <2 x i32> @llvm.ctpop.v2i32(<2 x i32>) define <2 x i1> @eq_or_non_0_commute(<2 x i32> %x) { ; CHECK-LABEL: @eq_or_non_0_commute( -; CHECK-NEXT: [[T0:%.*]] = tail call <2 x i32> @llvm.ctpop.v2i32(<2 x i32> [[X:%.*]]) -; CHECK-NEXT: [[CMP:%.*]] = icmp eq <2 x i32> [[T0]], -; CHECK-NEXT: [[NOTZERO:%.*]] = icmp ne <2 x i32> [[X]], zeroinitializer -; CHECK-NEXT: [[R:%.*]] = or <2 x i1> [[CMP]], [[NOTZERO]] -; CHECK-NEXT: ret <2 x i1> [[R]] +; CHECK-NEXT: [[NOTZERO:%.*]] = icmp ne <2 x i32> [[X:%.*]], zeroinitializer +; CHECK-NEXT: ret <2 x i1> [[NOTZERO]] ; %t0 = tail call <2 x i32> @llvm.ctpop.v2i32(<2 x i32> %x) %cmp = icmp eq <2 x i32> %t0, @@ -68,11 +62,8 @@ define i1 @eq_or_non_0_wrong_pred1(i32 %x) { define i1 @ne_and_is_0(i32 %x) { ; CHECK-LABEL: @ne_and_is_0( -; CHECK-NEXT: [[T0:%.*]] = tail call i32 @llvm.ctpop.i32(i32 [[X:%.*]]) -; CHECK-NEXT: [[CMP:%.*]] = icmp ne i32 [[T0]], 10 -; CHECK-NEXT: [[ISZERO:%.*]] = icmp eq i32 [[X]], 0 -; CHECK-NEXT: [[R:%.*]] = and i1 [[ISZERO]], [[CMP]] -; CHECK-NEXT: ret i1 [[R]] +; CHECK-NEXT: [[ISZERO:%.*]] = icmp eq i32 [[X:%.*]], 0 +; CHECK-NEXT: ret i1 [[ISZERO]] ; %t0 = tail call i32 @llvm.ctpop.i32(i32 %x) %cmp = icmp ne i32 %t0, 10 @@ -83,11 +74,8 @@ define i1 @ne_and_is_0(i32 %x) { define <2 x i1> @ne_and_is_0_commute(<2 x i32> %x) { ; CHECK-LABEL: @ne_and_is_0_commute( -; CHECK-NEXT: [[T0:%.*]] = tail call <2 x i32> @llvm.ctpop.v2i32(<2 x i32> [[X:%.*]]) -; CHECK-NEXT: [[CMP:%.*]] = icmp ne <2 x i32> [[T0]], -; CHECK-NEXT: [[ISZERO:%.*]] = icmp eq <2 x i32> [[X]], zeroinitializer -; CHECK-NEXT: [[R:%.*]] = and <2 x i1> [[CMP]], [[ISZERO]] -; CHECK-NEXT: ret <2 x i1> [[R]] +; CHECK-NEXT: [[ISZERO:%.*]] = icmp eq <2 x i32> [[X:%.*]], zeroinitializer +; CHECK-NEXT: ret <2 x i1> [[ISZERO]] ; %t0 = tail call <2 x i32> @llvm.ctpop.v2i32(<2 x i32> %x) %cmp = icmp ne <2 x i32> %t0,