File: safe-with-dep-distance.ll

package info (click to toggle)
llvm-toolchain-17 1%3A17.0.6-22
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,799,624 kB
  • sloc: cpp: 6,428,607; ansic: 1,383,196; asm: 793,408; python: 223,504; objc: 75,364; f90: 60,502; lisp: 33,869; pascal: 15,282; sh: 9,684; perl: 7,453; ml: 4,937; awk: 3,523; makefile: 2,889; javascript: 2,149; xml: 888; fortran: 619; cs: 573
file content (37 lines) | stat: -rw-r--r-- 1,084 bytes parent folder | download | duplicates (4)
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
32
33
34
35
36
37
; RUN: opt -passes='print<access-info>' -disable-output  < %s 2>&1 | FileCheck %s

; Analyze this loop:
;   for (i = 0; i < n; i++)
;    A[i + 4] = A[i] * 2;

; CHECK: Memory dependences are safe with a maximum dependence distance of 8 bytes

target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.10.0"

@A = common global ptr null, align 8

define void @f() {
entry:
  %a = load ptr, ptr @A, align 8
  br label %for.body

for.body:                                         ; preds = %for.body, %entry
  %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]

  %arrayidxA = getelementptr inbounds i16, ptr %a, i64 %ind
  %loadA = load i16, ptr %arrayidxA, align 2

  %mul = mul i16 %loadA, 2

  %next = add nuw nsw i64 %ind, 4
  %arrayidxA_next = getelementptr inbounds i16, ptr %a, i64 %next
  store i16 %mul, ptr %arrayidxA_next, align 2

  %add = add nuw nsw i64 %ind, 1
  %exitcond = icmp eq i64 %add, 20
  br i1 %exitcond, label %for.end, label %for.body

for.end:                                          ; preds = %for.body
  ret void
}