From 53e59a06437d7edbdf054e0375ea0ddeebe51819 Mon Sep 17 00:00:00 2001 From: David Majnemer Date: Mon, 20 Jun 2016 16:03:25 +0000 Subject: [PATCH] Reapply "[LoopIdiom] Don't remove dead operands manually" This reverts commit r273160, reapplying r273132. RecursivelyDeleteTriviallyDeadInstructions cannot be called on a parentless Instruction. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273162 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/LoopIdiomRecognize.cpp | 10 +--------- test/Transforms/LoopIdiom/pr28196.ll | 26 ++++++++++++++++++++++++++ 2 files changed, 27 insertions(+), 9 deletions(-) create mode 100644 test/Transforms/LoopIdiom/pr28196.ll diff --git a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp index f923673484f..d75dbb47771 100644 --- a/lib/Transforms/Scalar/LoopIdiomRecognize.cpp +++ b/lib/Transforms/Scalar/LoopIdiomRecognize.cpp @@ -150,17 +150,9 @@ INITIALIZE_PASS_END(LoopIdiomRecognize, "loop-idiom", "Recognize loop idioms", Pass *llvm::createLoopIdiomPass() { return new LoopIdiomRecognize(); } -/// deleteDeadInstruction - Delete this instruction. Before we do, go through -/// and zero out all the operands of this instruction. If any of them become -/// dead, delete them and the computation tree that feeds them. -/// -static void deleteDeadInstruction(Instruction *I, - const TargetLibraryInfo *TLI) { - SmallVector Operands(I->value_op_begin(), I->value_op_end()); +static void deleteDeadInstruction(Instruction *I) { I->replaceAllUsesWith(UndefValue::get(I->getType())); I->eraseFromParent(); - for (Value *Op : Operands) - RecursivelyDeleteTriviallyDeadInstructions(Op, TLI); } //===----------------------------------------------------------------------===// diff --git a/test/Transforms/LoopIdiom/pr28196.ll b/test/Transforms/LoopIdiom/pr28196.ll new file mode 100644 index 00000000000..10f49fbcd09 --- /dev/null +++ b/test/Transforms/LoopIdiom/pr28196.ll @@ -0,0 +1,26 @@ +; RUN: opt -loop-idiom -S < %s | FileCheck %s + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define void @test1() { +entry: + br label %for.body.preheader + +for.body.preheader: ; preds = %for.cond + br label %for.body + +for.body: ; preds = %for.body, %for.body.preheader + %indvars.iv = phi i32 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.body ] + %add.ptr3 = getelementptr inbounds i32, i32* null, i32 %indvars.iv + %add.ptr4 = getelementptr inbounds i32, i32* %add.ptr3, i32 1 + %0 = load i32, i32* %add.ptr4, align 4 + store i32 %0, i32* %add.ptr3, align 4 + %indvars.iv.next = add nsw i32 %indvars.iv, 1 + %exitcond = icmp ne i32 %indvars.iv.next, 6 + br i1 %exitcond, label %for.body, label %for.body.preheader +} + +; CHECK-LABEL: define void @test1( +; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* null, i8* inttoptr (i64 4 to i8*), i64 24, i32 4, i1 false) +; CHECK-NOT: store -- 2.11.0