File: 2006-01-19-ISelFoldingBug.ll

package info (click to toggle)
llvm-toolchain-19 1%3A19.1.7-3
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,998,520 kB
  • sloc: cpp: 6,951,680; ansic: 1,486,157; asm: 913,598; python: 232,024; f90: 80,126; objc: 75,281; lisp: 37,276; pascal: 16,990; sh: 10,009; ml: 5,058; perl: 4,724; awk: 3,523; makefile: 3,167; javascript: 2,504; xml: 892; fortran: 664; cs: 573
file content (31 lines) | stat: -rw-r--r-- 897 bytes parent folder | download | duplicates (13) 
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
 
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s | FileCheck %s
;
; Check that the isel does not fold the shld, which already folds a load
; and has two uses, into a store.

target triple = "i686-unknown-unknown"

@A = external dso_local global i32

define i32 @test5(i32 %B, i8 %C) {
; CHECK-LABEL: test5:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    movzbl {{[0-9]+}}(%esp), %ecx
; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %edx
; CHECK-NEXT:    movl A, %eax
; CHECK-NEXT:    shldl %cl, %edx, %eax
; CHECK-NEXT:    movl %eax, A
; CHECK-NEXT:    retl
entry:
  %tmp.1 = load i32, ptr @A
  %shift.upgrd.1 = zext i8 %C to i32
  %tmp.2 = shl i32 %tmp.1, %shift.upgrd.1
  %tmp.3 = sub i8 32, %C
  %shift.upgrd.2 = zext i8 %tmp.3 to i32
  %tmp.4 = lshr i32 %B, %shift.upgrd.2
  %tmp.5 = or i32 %tmp.4, %tmp.2
  store i32 %tmp.5, ptr @A
  ret i32 %tmp.5
}