File: 2009-11-12-MemDepMallocBitCast.ll

package info (click to toggle)
llvm-toolchain-7 1%3A7.0.1-8~deb9u3
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 733,456 kB
  • sloc: cpp: 3,776,651; ansic: 633,271; asm: 350,301; python: 142,716; objc: 107,612; sh: 22,626; lisp: 11,056; perl: 7,999; pascal: 6,742; ml: 5,537; awk: 3,536; makefile: 2,557; cs: 2,027; xml: 841; ruby: 156
file content (15 lines) | stat: -rw-r--r-- 606 bytes parent folder | download | duplicates (21)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
; Test to make sure malloc's bitcast does not block detection of a store 
; to aliased memory; GVN should not optimize away the load in this program.
; RUN: opt < %s -gvn -S | FileCheck %s

define i64 @test() {
  %1 = tail call i8* @malloc(i64 mul (i64 4, i64 ptrtoint (i64* getelementptr (i64, i64* null, i64 1) to i64))) ; <i8*> [#uses=2]
  store i8 42, i8* %1
  %X = bitcast i8* %1 to i64*                     ; <i64*> [#uses=1]
  %Y = load i64, i64* %X                               ; <i64> [#uses=1]
  ret i64 %Y
; CHECK: %Y = load i64, i64* %X
; CHECK: ret i64 %Y
}

declare noalias i8* @malloc(i64)