From 7e66c0d43aefce78948f0b73422f6e5bb28e2077 Mon Sep 17 00:00:00 2001 From: Evan Cheng Date: Mon, 5 Jan 2009 21:17:27 +0000 Subject: [PATCH] Find loop back edges only after empty blocks are eliminated. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61752 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/CodeGenPrepare.cpp | 5 +++-- test/CodeGen/X86/remat-mov0.ll | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp index ff9d32c316d..125b0760954 100644 --- a/lib/Transforms/Scalar/CodeGenPrepare.cpp +++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp @@ -125,12 +125,13 @@ void CodeGenPrepare::findLoopBackEdges(Function &F) { bool CodeGenPrepare::runOnFunction(Function &F) { bool EverMadeChange = false; - findLoopBackEdges(F); - // First pass, eliminate blocks that contain only PHI nodes and an // unconditional branch. EverMadeChange |= EliminateMostlyEmptyBlocks(F); + // Now find loop back edges. + findLoopBackEdges(F); + bool MadeChange = true; while (MadeChange) { MadeChange = false; diff --git a/test/CodeGen/X86/remat-mov0.ll b/test/CodeGen/X86/remat-mov0.ll index a50c8f3fa9c..360628cb6ae 100644 --- a/test/CodeGen/X86/remat-mov0.ll +++ b/test/CodeGen/X86/remat-mov0.ll @@ -1,4 +1,4 @@ -; RUN: llvm-as < %s | llc -march=x86 | grep xor | count 1 +; RUN: llvm-as < %s | llc -march=x86 | grep xor | count 2 %struct.FILE = type { i8*, i32, i32, i16, i16, %struct.__sbuf, i32, i8*, i32 (i8*)*, i32 (i8*, i8*, i32)*, i64 (i8*, i64, i32)*, i32 (i8*, i8*, i32)*, %struct.__sbuf, %struct.__sFILEX*, i32, [3 x i8], [1 x i8], %struct.__sbuf, i32, i64 } %struct.ImgT = type { i8, i8*, i8*, %struct.FILE*, i32, i32, i32, i32, i8*, double*, float*, float*, float*, i32*, double, double, i32*, double*, i32*, i32* } -- 2.11.0