From 7adb5c2aca8047ae184a96869e3cfcb034fbac39 Mon Sep 17 00:00:00 2001 From: Nikita Popov Date: Tue, 31 Dec 2019 17:42:38 +0100 Subject: [PATCH] Revert "[InstCombine] Fix infinite loop due to bitcast <-> phi transforms" This reverts commit 27a0795943fee0f30b995fe5165428afc2dfd402. Seems to break test-suite. --- .../Transforms/InstCombine/InstCombineCasts.cpp | 6 - llvm/test/Transforms/InstCombine/pr44245.ll | 142 --------------------- 2 files changed, 148 deletions(-) delete mode 100644 llvm/test/Transforms/InstCombine/pr44245.ll diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp index 446e675..3ba56bb 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -2370,12 +2370,6 @@ Instruction *InstCombiner::optimizeBitCastFromPhi(CastInst &CI, PHINode *PN) { llvm_unreachable("all uses should be handled"); } } - - // At this point the old phi has either no users, or is only used - // in other old phis. Replace with undef to break circles and remove - // the instruction. - replaceInstUsesWith(*OldPN, UndefValue::get(OldPN->getType())); - eraseInstFromFunction(*OldPN); } return RetVal; diff --git a/llvm/test/Transforms/InstCombine/pr44245.ll b/llvm/test/Transforms/InstCombine/pr44245.ll deleted file mode 100644 index 3b9e252..0000000 --- a/llvm/test/Transforms/InstCombine/pr44245.ll +++ /dev/null @@ -1,142 +0,0 @@ -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py -; RUN: opt -S -instcombine < %s | FileCheck %s - -; This used to cause on infinite instcombine loop. - -define void @test(i1 %c) { -; CHECK-LABEL: @test( -; CHECK-NEXT: bb16: -; CHECK-NEXT: br i1 [[C:%.*]], label [[BB17:%.*]], label [[BB24:%.*]] -; CHECK: bb17: -; CHECK-NEXT: [[TMP0:%.*]] = phi i8* [ [[TMP1:%.*]], [[BB47:%.*]] ], [ undef, [[BB16:%.*]] ] -; CHECK-NEXT: store i8* [[TMP0]], i8** undef, align 8 -; CHECK-NEXT: ret void -; CHECK: bb24: -; CHECK-NEXT: br i1 [[C]], label [[BB44:%.*]], label [[BB49:%.*]] -; CHECK: bb44: -; CHECK-NEXT: [[TMP469:%.*]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb47: -; CHECK-NEXT: [[TMP1]] = phi i8* [ [[TMP2:%.*]], [[BB150:%.*]] ], [ [[TMP1223:%.*]], [[BB119:%.*]] ], [ [[TMP1034:%.*]], [[BB101:%.*]] ], [ [[TMP935:%.*]], [[BB91:%.*]] ], [ [[TMP836:%.*]], [[BB81:%.*]] ], [ [[TMP707:%.*]], [[BB67:%.*]] ], [ [[TMP588:%.*]], [[BB56:%.*]] ], [ [[TMP469]], [[BB44]] ] -; CHECK-NEXT: br label [[BB17]] -; CHECK: bb49: -; CHECK-NEXT: br i1 [[C]], label [[BB56]], label [[BB59:%.*]] -; CHECK: bb56: -; CHECK-NEXT: [[TMP588]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb59: -; CHECK-NEXT: br i1 [[C]], label [[BB67]], label [[BB71:%.*]] -; CHECK: bb67: -; CHECK-NEXT: [[TMP707]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb71: -; CHECK-NEXT: br i1 [[C]], label [[BB81]], label [[BB84:%.*]] -; CHECK: bb81: -; CHECK-NEXT: [[TMP836]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb84: -; CHECK-NEXT: br i1 [[C]], label [[BB91]], label [[BB94:%.*]] -; CHECK: bb91: -; CHECK-NEXT: [[TMP935]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb94: -; CHECK-NEXT: br i1 [[C]], label [[BB101]], label [[BB104:%.*]] -; CHECK: bb101: -; CHECK-NEXT: [[TMP1034]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb104: -; CHECK-NEXT: br i1 [[C]], label [[BB119]], label [[BB123:%.*]] -; CHECK: bb119: -; CHECK-NEXT: [[TMP1223]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb123: -; CHECK-NEXT: br i1 [[C]], label [[BB147:%.*]], label [[BB152:%.*]] -; CHECK: bb147: -; CHECK-NEXT: [[TMP1492:%.*]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: br label [[BB150]] -; CHECK: bb150: -; CHECK-NEXT: [[TMP2]] = phi i8* [ [[TMP1841:%.*]], [[BB152]] ], [ [[TMP1492]], [[BB147]] ] -; CHECK-NEXT: br label [[BB47]] -; CHECK: bb152: -; CHECK-NEXT: [[TMP1841]] = load i8*, i8** inttoptr (i64 16 to i8**), align 16 -; CHECK-NEXT: call void undef() -; CHECK-NEXT: br label [[BB150]] -; -bb16: ; preds = %bb - br i1 %c, label %bb17, label %bb24 - -bb17: ; preds = %bb47, %bb17 - %0 = phi i8* [ %1, %bb47 ], [ undef, %bb16 ] - store i8* %0, i8** undef, align 8 - ret void - -bb24: ; preds = %bb24 - br i1 %c, label %bb44, label %bb49 - -bb44: ; preds = %bb43 - %tmp46 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb47: ; preds = %bb150, %bb119, %bb101, %bb91, %bb81, %bb67, %bb56, %bb44 - %.in1 = phi i64* [ %.in, %bb150 ], [ %tmp122, %bb119 ], [ %tmp103, %bb101 ], [ %tmp93, %bb91 ], [ %tmp83, %bb81 ], [ %tmp70, %bb67 ], [ %tmp58, %bb56 ], [ %tmp46, %bb44 ] - %1 = bitcast i64* %.in1 to i8* - br label %bb17 - -bb49: ; preds = %bb49 - br i1 %c, label %bb56, label %bb59 - -bb56: ; preds = %bb55 - %tmp58 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb59: ; preds = %bb59 - br i1 %c, label %bb67, label %bb71 - -bb67: ; preds = %bb66 - %tmp70 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb71: ; preds = %bb71 - br i1 %c, label %bb81, label %bb84 - -bb81: ; preds = %bb80 - %tmp83 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb84: ; preds = %bb84 - br i1 %c, label %bb91, label %bb94 - -bb91: ; preds = %bb90 - %tmp93 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb94: ; preds = %bb94 - br i1 %c, label %bb101, label %bb104 - -bb101: ; preds = %bb100 - %tmp103 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb104: ; preds = %bb104 - br i1 %c, label %bb119, label %bb123 - -bb119: ; preds = %bb118 - %tmp122 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb47 - -bb123: ; preds = %bb123 - br i1 %c, label %bb147, label %bb152 - -bb147: ; preds = %bb146 - %tmp149 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - br label %bb150 - -bb150: ; preds = %bb152, %bb147 - %.in = phi i64* [ %tmp184, %bb152 ], [ %tmp149, %bb147 ] - br label %bb47 - -bb152: ; preds = %bb146 - %tmp184 = load i64*, i64** inttoptr (i64 16 to i64**), align 16 - call void undef() - br label %bb150 -} -- 2.7.4