File: purecse.ll

package info (click to toggle)
llvm-toolchain-14 1%3A14.0.6-12
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 1,496,180 kB
  • sloc: cpp: 5,593,972; ansic: 986,872; asm: 585,869; python: 184,223; objc: 72,530; lisp: 31,119; f90: 27,793; javascript: 9,780; pascal: 9,762; sh: 9,482; perl: 7,468; ml: 5,432; awk: 3,523; makefile: 2,538; xml: 953; cs: 573; fortran: 567
file content (27 lines) | stat: -rw-r--r-- 954 bytes parent folder | download | duplicates (8) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
 
; Test that pure functions are cse'd away
; RUN: opt < %s -disable-basic-aa -globals-aa -gvn -instcombine -S | FileCheck %s

define i32 @pure(i32 %X) {
        %Y = add i32 %X, 1              ; <i32> [#uses=1]
        ret i32 %Y
}

define i32 @test1(i32 %X) {
; CHECK:      %A = call i32 @pure(i32 %X)
; CHECK-NEXT: ret i32 0
        %A = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
        %B = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
        %C = sub i32 %A, %B             ; <i32> [#uses=1]
        ret i32 %C
}

define i32 @test2(i32 %X, i32* %P) {
; CHECK:      %A = call i32 @pure(i32 %X)
; CHECK-NEXT: store i32 %X, i32* %P
; CHECK-NEXT: ret i32 0
        %A = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
        store i32 %X, i32* %P ;; Does not invalidate 'pure' call.
        %B = call i32 @pure( i32 %X )           ; <i32> [#uses=1]
        %C = sub i32 %A, %B             ; <i32> [#uses=1]
        ret i32 %C
}