File: 2002-05-15-SubReassociate.ll

package info (click to toggle)
llvm-toolchain-9 1%3A9.0.1-16.1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 882,388 kB
  • sloc: cpp: 4,167,636; ansic: 714,256; asm: 457,610; python: 155,927; objc: 65,094; sh: 42,856; lisp: 26,908; perl: 7,786; pascal: 7,722; makefile: 6,881; ml: 5,581; awk: 3,648; cs: 2,027; xml: 888; javascript: 381; ruby: 156
file content (31 lines) | stat: -rw-r--r-- 856 bytes parent folder | download | duplicates (6)
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
28
29
30
31
; RUN: opt < %s -reassociate -constprop -instcombine -dce -S | FileCheck %s

; With sub reassociation, constant folding can eliminate all of the constants.
define i32 @test1(i32 %A, i32 %B) {
; CHECK-LABEL: @test1(
; CHECK-NEXT:    [[Z:%.*]] = sub i32 %A, %B
; CHECK-NEXT:    ret i32 [[Z]]
;
  %W = add i32 5, %B
  %X = add i32 -7, %A
  %Y = sub i32 %X, %W
  %Z = add i32 %Y, 12
  ret i32 %Z
}

; With sub reassociation, constant folding can eliminate the two 12 constants.
define i32 @test2(i32 %A, i32 %B, i32 %C, i32 %D) {
; CHECK-LABEL: @test2(
; CHECK-NEXT:    [[SUM:%.*]] = add i32 %B, %A
; CHECK-NEXT:    [[SUM1:%.*]] = add i32 [[SUM]], %C
; CHECK-NEXT:    [[Q:%.*]] = sub i32 %D, [[SUM1]]
; CHECK-NEXT:    ret i32 [[Q]]
;
  %M = add i32 %A, 12
  %N = add i32 %M, %B
  %O = add i32 %N, %C
  %P = sub i32 %D, %O
  %Q = add i32 %P, 12
  ret i32 %Q
}