File: 2005-01-17-CycleInDAG.ll

package info (click to toggle)
llvm-toolchain-3.8 1%3A3.8.1-24
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 379,280 kB
  • ctags: 388,501
  • sloc: cpp: 2,309,705; ansic: 477,070; objc: 100,918; asm: 97,974; python: 95,911; sh: 18,634; makefile: 7,294; perl: 5,584; ml: 5,460; pascal: 4,661; lisp: 2,548; xml: 686; cs: 350; php: 212; csh: 117
file content (17 lines) | stat: -rw-r--r-- 682 bytes parent folder | download | duplicates (6)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
; This testcase was distilled from 132.ijpeg.  Bsaically we cannot fold the
; load into the sub instruction here as it induces a cycle in the dag, which
; is invalid code (there is no correct way to order the instruction).  Check
; that we do not fold the load into the sub.

; RUN: llc < %s -march=x86 | not grep sub.*GLOBAL

@GLOBAL = external global i32           ; <i32*> [#uses=1]

define i32 @test(i32* %P1, i32* %P2, i32* %P3) nounwind {
        %L = load i32, i32* @GLOBAL          ; <i32> [#uses=1]
        store i32 12, i32* %P2
        %Y = load i32, i32* %P3              ; <i32> [#uses=1]
        %Z = sub i32 %Y, %L             ; <i32> [#uses=1]
        ret i32 %Z
}