From e9abc8177a368ea481dfa3874ce10a84e032fb01 Mon Sep 17 00:00:00 2001 From: Craig Topper Date: Wed, 24 Jul 2019 20:57:29 +0000 Subject: [PATCH] [InstCombine] Teach foldOrOfICmps to allow icmp eq MIN_INT/MAX to be part of a range comparision. Similar for foldAndOfICmps We can treat icmp eq X, MIN_UINT as icmp ule X, MIN_UINT and allow it to merge with icmp ugt X, C. Similar for the other constants. We can do simliar for icmp ne X, (U)INT_MIN/MAX in foldAndOfICmps. And we already handled UINT_MIN there. Fixes PR42691. Differential Revision: https://reviews.llvm.org/D65017 llvm-svn: 366945 --- .../Transforms/InstCombine/InstCombineAndOrXor.cpp | 48 ++++++++++++++++++---- llvm/test/Transforms/InstCombine/and-or-icmps.ll | 47 +++++++++------------ 2 files changed, 59 insertions(+), 36 deletions(-) diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 9db0824..68cd424 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -1197,7 +1197,7 @@ Value *InstCombiner::foldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS, // (X != 13 & X u< 14) -> X < 13 if (LHSC->getValue() == (RHSC->getValue() - 1)) return Builder.CreateICmpULT(LHS0, LHSC); - if (LHSC->isZero()) // (X != 0 & X u< 14) -> X-1 u< 13 + if (LHSC->isZero()) // (X != 0 & X u< C) -> X-1 u< C-1 return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue(), false, true); break; // (X != 13 & X u< 15) -> no change @@ -1205,7 +1205,11 @@ Value *InstCombiner::foldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS, // (X != 13 & X s< 14) -> X < 13 if (LHSC->getValue() == (RHSC->getValue() - 1)) return Builder.CreateICmpSLT(LHS0, LHSC); - break; // (X != 13 & X s< 15) -> no change + // (X != INT_MIN & X s< C) -> X-(INT_MIN+1) u< (C-(INT_MIN+1)) + if (LHSC->isMinValue(true)) + return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue(), + true, true); + break; // (X != 13 & X s< 15) -> no change case ICmpInst::ICMP_NE: // Potential folds for this case should already be handled. break; @@ -1219,8 +1223,12 @@ Value *InstCombiner::foldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS, // (X u> 13 & X != 14) -> X u> 14 if (RHSC->getValue() == (LHSC->getValue() + 1)) return Builder.CreateICmp(PredL, LHS0, RHSC); + // X u> C & X != UINT_MAX -> (X-(C+1)) u< UINT_MAX-(C+1) + if (RHSC->isMaxValue(false)) + return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue(), + false, true); break; // (X u> 13 & X != 15) -> no change - case ICmpInst::ICMP_ULT: // (X u> 13 & X u< 15) -> (X-14) 13 & X u< 15) -> (X-14) u< 1 return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue(), false, true); } @@ -1233,8 +1241,12 @@ Value *InstCombiner::foldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS, // (X s> 13 & X != 14) -> X s> 14 if (RHSC->getValue() == (LHSC->getValue() + 1)) return Builder.CreateICmp(PredL, LHS0, RHSC); + // X s> C & X != INT_MAX -> (X-(C+1)) u< INT_MAX-(C+1) + if (RHSC->isMaxValue(true)) + return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue(), + true, true); break; // (X s> 13 & X != 15) -> no change - case ICmpInst::ICMP_SLT: // (X s> 13 & X s< 15) -> (X-14) s< 1 + case ICmpInst::ICMP_SLT: // (X s> 13 & X s< 15) -> (X-14) u< 1 return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue(), true, true); } @@ -2253,8 +2265,19 @@ Value *InstCombiner::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, case ICmpInst::ICMP_EQ: // Potential folds for this case should already be handled. break; - case ICmpInst::ICMP_UGT: // (X == 13 | X u> 14) -> no change - case ICmpInst::ICMP_SGT: // (X == 13 | X s> 14) -> no change + case ICmpInst::ICMP_UGT: + // (X == 0 || X u> C) -> (X-1) u>= C + if (LHSC->isMinValue(false)) + return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue() + 1, + false, false); + // (X == 13 | X u> 14) -> no change + break; + case ICmpInst::ICMP_SGT: + // (X == INT_MIN || X s> C) -> (X-(INT_MIN+1)) u>= C-INT_MIN + if (LHSC->isMinValue(true)) + return insertRangeTest(LHS0, LHSC->getValue() + 1, RHSC->getValue() + 1, + true, false); + // (X == 13 | X s> 14) -> no change break; } break; @@ -2263,6 +2286,10 @@ Value *InstCombiner::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, default: llvm_unreachable("Unknown integer condition code!"); case ICmpInst::ICMP_EQ: // (X u< 13 | X == 14) -> no change + // (X u< C || X == UINT_MAX) => (X-C) u>= UINT_MAX-C + if (RHSC->isMaxValue(false)) + return insertRangeTest(LHS0, LHSC->getValue(), RHSC->getValue(), + false, false); break; case ICmpInst::ICMP_UGT: // (X u< 13 | X u> 15) -> (X-13) u> 2 assert(!RHSC->isMaxValue(false) && "Missed icmp simplification"); @@ -2274,9 +2301,14 @@ Value *InstCombiner::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, switch (PredR) { default: llvm_unreachable("Unknown integer condition code!"); - case ICmpInst::ICMP_EQ: // (X s< 13 | X == 14) -> no change + case ICmpInst::ICMP_EQ: + // (X s< C || X == INT_MAX) => (X-C) u>= INT_MAX-C + if (RHSC->isMaxValue(true)) + return insertRangeTest(LHS0, LHSC->getValue(), RHSC->getValue(), + true, false); + // (X s< 13 | X == 14) -> no change break; - case ICmpInst::ICMP_SGT: // (X s< 13 | X s> 15) -> (X-13) s> 2 + case ICmpInst::ICMP_SGT: // (X s< 13 | X s> 15) -> (X-13) u> 2 assert(!RHSC->isMaxValue(true) && "Missed icmp simplification"); return insertRangeTest(LHS0, LHSC->getValue(), RHSC->getValue() + 1, true, false); diff --git a/llvm/test/Transforms/InstCombine/and-or-icmps.ll b/llvm/test/Transforms/InstCombine/and-or-icmps.ll index 481e0f2..378b820 100644 --- a/llvm/test/Transforms/InstCombine/and-or-icmps.ll +++ b/llvm/test/Transforms/InstCombine/and-or-icmps.ll @@ -255,10 +255,8 @@ define void @simplify_before_foldAndOfICmps() { define i1 @PR42691_1(i32 %x) { ; CHECK-LABEL: @PR42691_1( -; CHECK-NEXT: [[C1:%.*]] = icmp slt i32 %x, 0 -; CHECK-NEXT: [[C2:%.*]] = icmp eq i32 %x, 2147483647 -; CHECK-NEXT: [[C:%.*]] = or i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[TMP1:%.*]] = icmp ugt i32 %x, 2147483646 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp slt i32 %x, 0 %c2 = icmp eq i32 %x, 2147483647 @@ -279,10 +277,8 @@ define i1 @PR42691_2(i32 %x) { define i1 @PR42691_3(i32 %x) { ; CHECK-LABEL: @PR42691_3( -; CHECK-NEXT: [[C1:%.*]] = icmp sgt i32 %x, -1 -; CHECK-NEXT: [[C2:%.*]] = icmp eq i32 %x, -2147483648 -; CHECK-NEXT: [[C:%.*]] = or i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 %x, -2147483647 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp sge i32 %x, 0 %c2 = icmp eq i32 %x, -2147483648 @@ -303,10 +299,9 @@ define i1 @PR42691_4(i32 %x) { define i1 @PR42691_5(i32 %x) { ; CHECK-LABEL: @PR42691_5( -; CHECK-NEXT: [[C1:%.*]] = icmp slt i32 %x, 1 -; CHECK-NEXT: [[C2:%.*]] = icmp eq i32 %x, 2147483647 -; CHECK-NEXT: [[C:%.*]] = or i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[X_OFF:%.*]] = add i32 %x, -1 +; CHECK-NEXT: [[TMP1:%.*]] = icmp ugt i32 [[X_OFF]], 2147483645 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp slt i32 %x, 1 %c2 = icmp eq i32 %x, 2147483647 @@ -316,10 +311,9 @@ define i1 @PR42691_5(i32 %x) { define i1 @PR42691_6(i32 %x) { ; CHECK-LABEL: @PR42691_6( -; CHECK-NEXT: [[C1:%.*]] = icmp ult i32 %x, -2147483647 -; CHECK-NEXT: [[C2:%.*]] = icmp eq i32 %x, -1 -; CHECK-NEXT: [[C:%.*]] = or i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[X_OFF:%.*]] = add i32 %x, 2147483647 +; CHECK-NEXT: [[TMP1:%.*]] = icmp ugt i32 [[X_OFF]], 2147483645 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp ult i32 %x, 2147483649 %c2 = icmp eq i32 %x, 4294967295 @@ -341,10 +335,9 @@ define i1 @PR42691_7(i32 %x) { define i1 @PR42691_8(i32 %x) { ; CHECK-LABEL: @PR42691_8( -; CHECK-NEXT: [[C1:%.*]] = icmp slt i32 %x, 14 -; CHECK-NEXT: [[C2:%.*]] = icmp ne i32 %x, -2147483648 -; CHECK-NEXT: [[C:%.*]] = and i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[X_OFF:%.*]] = add i32 %x, 2147483647 +; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[X_OFF]], -2147483635 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp slt i32 %x, 14 %c2 = icmp ne i32 %x, -2147483648 @@ -354,10 +347,9 @@ define i1 @PR42691_8(i32 %x) { define i1 @PR42691_9(i32 %x) { ; CHECK-LABEL: @PR42691_9( -; CHECK-NEXT: [[C1:%.*]] = icmp sgt i32 %x, 13 -; CHECK-NEXT: [[C2:%.*]] = icmp ne i32 %x, 2147483647 -; CHECK-NEXT: [[C:%.*]] = and i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[X_OFF:%.*]] = add i32 %x, -14 +; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[X_OFF]], 2147483633 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp sgt i32 %x, 13 %c2 = icmp ne i32 %x, 2147483647 @@ -367,10 +359,9 @@ define i1 @PR42691_9(i32 %x) { define i1 @PR42691_10(i32 %x) { ; CHECK-LABEL: @PR42691_10( -; CHECK-NEXT: [[C1:%.*]] = icmp ugt i32 %x, 13 -; CHECK-NEXT: [[C2:%.*]] = icmp ne i32 %x, -1 -; CHECK-NEXT: [[C:%.*]] = and i1 [[C1]], [[C2]] -; CHECK-NEXT: ret i1 [[C]] +; CHECK-NEXT: [[X_OFF:%.*]] = add i32 %x, -14 +; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[X_OFF]], -15 +; CHECK-NEXT: ret i1 [[TMP1]] ; %c1 = icmp ugt i32 %x, 13 %c2 = icmp ne i32 %x, 4294967295 -- 2.7.4