llvm-6502/test/Transforms/InstCombine/malloc-free-delete.ll
Nick Lewycky d5061a9268 Fix logical error when detecting lifetime intrinsics.
Don't replace a gep/bitcast with 'undef' because that will form a "free(undef)"
which in turn means "unreachable". What we wanted was a no-op. Instead, analyze
the whole tree and look for all the instructions we need to delete first, then
delete them second, not relying on the use_list to stay consistent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136752 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-03 00:43:35 +00:00

49 lines
1.1 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
; PR1201
define i32 @main(i32 %argc, i8** %argv) {
%c_19 = alloca i8*
%malloc_206 = tail call i8* @malloc(i32 mul (i32 ptrtoint (i8* getelementptr (i8* null, i32 1) to i32), i32 10))
store i8* %malloc_206, i8** %c_19
%tmp_207 = load i8** %c_19
tail call void @free(i8* %tmp_207)
ret i32 0
; CHECK-NOT: malloc
; CHECK-NOT: free
; CHECK: ret i32 0
}
declare noalias i8* @malloc(i32)
declare void @free(i8*)
define i1 @foo() {
; CHECK: @foo
; CHECK-NEXT: ret i1 false
%m = call i8* @malloc(i32 1)
%z = icmp eq i8* %m, null
call void @free(i8* %m)
ret i1 %z
}
declare void @llvm.lifetime.start(i64, i8*)
declare void @llvm.lifetime.end(i64, i8*)
define void @test3() {
; CHECK: @test3
; CHECK-NEXT: ret void
%a = call noalias i8* @malloc(i32 10)
call void @llvm.lifetime.start(i64 10, i8* %a)
call void @llvm.lifetime.end(i64 10, i8* %a)
ret void
}
;; This used to crash.
define void @test4() {
; CHECK: @test4
; CHECK-NEXT: ret void
%A = call i8* @malloc(i32 16000)
%B = bitcast i8* %A to double*
%C = bitcast double* %B to i8*
call void @free(i8* %C)
ret void
}