llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-llvm-transforms <details> <summary>Changes</summary> This patch simplifies the overflow check of unsigned addition. `a + b <u a` implies `a + b <u b` `a + b >=u a` implies `a + b >=u b` Alive2: https://alive2.llvm.org/ce/z/H8oK8n Fixes #<!-- -->65863. --- Full diff: https://github.com/llvm/llvm-project/pull/65910.diff 2 Files Affected: - (modified) llvm/lib/Analysis/ValueTracking.cpp (+23) - (modified) llvm/test/Transforms/InstSimplify/and-or-implied-cond.ll (+8-24) ``````````diff diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index c4153b824c37e0a..5aaff4ee81be969 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -8291,6 +8291,29 @@ static std::optional<bool> isImpliedCondICmps(const ICmpInst *LHS, if (L0 == R0 && match(L1, m_APInt(LC)) && match(R1, m_APInt(RC))) return isImpliedCondCommonOperandWithConstants(LPred, *LC, RPred, *RC); + // L0 = R0 = L1 + R1, L0 >=u L1 implies R0 >=u R1, L0 <u L1 implies R0 <u R1 + if (ICmpInst::isUnsigned(LPred) && ICmpInst::isUnsigned(RPred)) { + if (L0 == R1) { + std::swap(R0, R1); + RPred = ICmpInst::getSwappedPredicate(RPred); + } + if (L1 == R0) { + std::swap(L0, L1); + LPred = ICmpInst::getSwappedPredicate(LPred); + } + if (L1 == R1) { + std::swap(L0, L1); + LPred = ICmpInst::getSwappedPredicate(LPred); + std::swap(R0, R1); + RPred = ICmpInst::getSwappedPredicate(RPred); + } + if (L0 == R0 && + (LPred == ICmpInst::ICMP_UGE || LPred == ICmpInst::ICMP_ULT) && + (RPred == ICmpInst::ICMP_ULT || RPred == ICmpInst::ICMP_UGE) && + match(L0, m_c_Add(m_Specific(L1), m_Specific(R1)))) + return LPred == RPred; + } + if (LPred == RPred) return isImpliedCondOperands(LPred, L0, L1, R0, R1, DL, Depth); diff --git a/llvm/test/Transforms/InstSimplify/and-or-implied-cond.ll b/llvm/test/Transforms/InstSimplify/and-or-implied-cond.ll index 4a6610250df559a..df442dd8f185c81 100644 --- a/llvm/test/Transforms/InstSimplify/and-or-implied-cond.ll +++ b/llvm/test/Transforms/InstSimplify/and-or-implied-cond.ll @@ -131,9 +131,7 @@ define i1 @uaddo_and(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_and( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp uge i64 [[S]], [[A]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp uge i64 [[S]], [[B]] -; CHECK-NEXT: [[COND:%.*]] = and i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp uge i64 %s, %a @@ -146,9 +144,7 @@ define i1 @uaddo_and_commuted1(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_and_commuted1( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp ule i64 [[A]], [[S]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp uge i64 [[S]], [[B]] -; CHECK-NEXT: [[COND:%.*]] = and i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp ule i64 %a, %s @@ -161,9 +157,7 @@ define i1 @uaddo_and_commuted2(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_and_commuted2( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp uge i64 [[S]], [[A]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp ule i64 [[B]], [[S]] -; CHECK-NEXT: [[COND:%.*]] = and i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp uge i64 %s, %a @@ -176,9 +170,7 @@ define i1 @uaddo_and_commuted3(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_and_commuted3( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp ule i64 [[A]], [[S]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp ule i64 [[B]], [[S]] -; CHECK-NEXT: [[COND:%.*]] = and i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp ule i64 %a, %s @@ -191,9 +183,7 @@ define i1 @uaddo_or(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_or( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp ult i64 [[S]], [[A]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp ult i64 [[S]], [[B]] -; CHECK-NEXT: [[COND:%.*]] = or i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp ult i64 %s, %a @@ -206,9 +196,7 @@ define i1 @uaddo_or_commuted1(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_or_commuted1( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp ugt i64 [[A]], [[S]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp ult i64 [[S]], [[B]] -; CHECK-NEXT: [[COND:%.*]] = or i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp ugt i64 %a, %s @@ -221,9 +209,7 @@ define i1 @uaddo_or_commuted2(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_or_commuted2( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp ult i64 [[S]], [[A]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp ugt i64 [[B]], [[S]] -; CHECK-NEXT: [[COND:%.*]] = or i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp ult i64 %s, %a @@ -236,9 +222,7 @@ define i1 @uaddo_or_commuted3(i64 %a, i64 %b){ ; CHECK-LABEL: @uaddo_or_commuted3( ; CHECK-NEXT: [[S:%.*]] = add i64 [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[COND_A:%.*]] = icmp ugt i64 [[A]], [[S]] -; CHECK-NEXT: [[COND_B:%.*]] = icmp ugt i64 [[B]], [[S]] -; CHECK-NEXT: [[COND:%.*]] = or i1 [[COND_A]], [[COND_B]] -; CHECK-NEXT: ret i1 [[COND]] +; CHECK-NEXT: ret i1 [[COND_A]] ; %s = add i64 %a, %b %cond_a = icmp ugt i64 %a, %s `````````` </details> https://github.com/llvm/llvm-project/pull/65910 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
