File: pre-no-cost-phi.ll

package info (click to toggle)
llvm-toolchain-18 1%3A18.1.8-18
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,908,340 kB
  • sloc: cpp: 6,667,937; ansic: 1,440,452; asm: 883,619; python: 230,549; objc: 76,880; f90: 74,238; lisp: 35,989; pascal: 16,571; sh: 10,229; perl: 7,459; ml: 5,047; awk: 3,523; makefile: 2,987; javascript: 2,149; xml: 892; fortran: 649; cs: 573
file content (31 lines) | stat: -rw-r--r-- 715 bytes parent folder | download | duplicates (15) 
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 -passes=gvn -S | FileCheck %s
; This testcase tests insertion of no-cost phis.  That is,
; when the value is already available in every predecessor,
; and we just need to insert a phi node to merge the available values.

@c = global i32 0, align 4
@d = global i32 0, align 4


define i32 @mai(i32 %foo, i32 %a, i32 %b) {
  %1 = icmp ne i32 %foo, 0
  br i1 %1, label %bb1, label %bb2

bb1:
  %2 = add nsw i32 %a, %b
  store i32 %2, ptr @c, align 4
  br label %mergeblock

bb2:
  %3 = add nsw i32 %a, %b
  store i32 %3, ptr @d, align 4
  br label %mergeblock

mergeblock:
; CHECK: pre-phi = phi i32 [ %3, %bb2 ], [ %2, %bb1 ]
; CHECK-NEXT: ret i32 %.pre-phi
  %4 = add nsw i32 %a, %b
  ret i32 %4
}