llvm-mirror/test/Transforms/DeadStoreElimination/free.ll
Eli Friedman 9889f09e8d [DSE] Don't remove stores made live by a call which unwinds.
Issue exposed by noalias or more aggressive alias analysis.

Fixes http://llvm.org/PR25422.

Differential revision: https://reviews.llvm.org/D21007

llvm-svn: 278451
2016-08-12 01:09:53 +00:00

71 lines
1.5 KiB
LLVM

; RUN: opt < %s -basicaa -dse -S | FileCheck %s
target datalayout = "e-p:64:64:64"
declare void @free(i8* nocapture)
declare noalias i8* @malloc(i64)
; CHECK-LABEL: @test(
; CHECK-NEXT: bitcast
; CHECK-NEXT: @free
; CHECK-NEXT: ret void
define void @test(i32* %Q, i32* %P) {
%DEAD = load i32, i32* %Q ; <i32> [#uses=1]
store i32 %DEAD, i32* %P
%1 = bitcast i32* %P to i8*
tail call void @free(i8* %1) nounwind
ret void
}
; CHECK-LABEL: @test2(
; CHECK-NEXT: bitcast
; CHECK-NEXT: @free
; CHECK-NEXT: ret void
define void @test2({i32, i32}* %P) {
%Q = getelementptr {i32, i32}, {i32, i32} *%P, i32 0, i32 1
store i32 4, i32* %Q
%1 = bitcast {i32, i32}* %P to i8*
tail call void @free(i8* %1) nounwind
ret void
}
; CHECK-LABEL: @test3(
; CHECK-NOT: store
; CHECK: ret void
define void @test3() {
%m = call i8* @malloc(i64 24)
store i8 0, i8* %m
%m1 = getelementptr i8, i8* %m, i64 1
store i8 1, i8* %m1
call void @free(i8* %m) nounwind
ret void
}
; PR11240
; CHECK-LABEL: @test4(
; CHECK-NOT: store
; CHECK: ret void
define void @test4(i1 %x) nounwind {
entry:
%alloc1 = tail call noalias i8* @malloc(i64 4) nounwind
br i1 %x, label %skipinit1, label %init1
init1:
store i8 1, i8* %alloc1
br label %skipinit1
skipinit1:
tail call void @free(i8* %alloc1) nounwind
ret void
}
; CHECK-LABEL: @test5(
define void @test5() {
br label %bb
bb:
tail call void @free(i8* undef) nounwind
br label %bb
}