File: 2003-02-26-AccessSizeTest.ll

package info (click to toggle)
llvm-toolchain-15 1%3A15.0.6-4
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 1,554,644 kB
  • sloc: cpp: 5,922,452; ansic: 1,012,136; asm: 674,362; python: 191,568; objc: 73,855; f90: 42,327; lisp: 31,913; pascal: 11,973; javascript: 10,144; sh: 9,421; perl: 7,447; ml: 5,527; awk: 3,523; makefile: 2,520; xml: 885; cs: 573; fortran: 567
file content (20 lines) | stat: -rw-r--r-- 661 bytes parent folder | download | duplicates (9)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
; This testcase makes sure that size is taken to account when alias analysis 
; is performed.  It is not legal to delete the second load instruction because
; the value computed by the first load instruction is changed by the store.

; RUN: opt < %s -basic-aa -gvn -instcombine -S | FileCheck %s

define i32 @test() {
; CHECK: %Y.DONOTREMOVE = load i32, i32* %A
; CHECK: %Z = sub i32 0, %Y.DONOTREMOVE
  %A = alloca i32
  store i32 0, i32* %A
  %X = load i32, i32* %A
  %B = bitcast i32* %A to i8*
  %C = getelementptr i8, i8* %B, i64 1
  store i8 1, i8* %C    ; Aliases %A
  %Y.DONOTREMOVE = load i32, i32* %A
  %Z = sub i32 %X, %Y.DONOTREMOVE
  ret i32 %Z
}