File: extractelement-legalization-cycle.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 (21 lines) | stat: -rw-r--r-- 870 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
 
; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s

; When the extractelement is converted to a load the store can be re-used.
; This will, however, introduce a cycle into the selection DAG (the load
; of the extractelement index is dependent on the store, and so after the
; conversion it becomes dependent on the new load, which is dependent on
; the index).  Make sure we skip the store, and conservatively instead
; use a store to the stack.

define float @foo(ptr %i, ptr %v) {
; CHECK-LABEL: foo:
; CHECK:    movaps %xmm0, -[[OFFSET:[0-9]+]](%rsp)
; CHECK:    movss -[[OFFSET]](%rsp,{{.*}}), %xmm0 {{.*}}
; CHECK-NEXT:    retq
  %1 = load <4 x float>, ptr %v, align 16
  %mul = fmul <4 x float> %1, %1
  store <4 x float> %mul, ptr %v, align 16
  %2 = load i32, ptr %i, align 4
  %vecext = extractelement <4 x float> %mul, i32 %2
  ret float %vecext
}