llvm-6502/test/CodeGen/X86/isel-optnone.ll
Paul Robinson 16c7e0b48c Teach ISel not to optimize 'optnone' functions (revised).
Improvements over r195317:
- Set/restore EnableFastISel flag instead of just running FastISel within
  SelectAllBasicBlocks; the flag is checked in various places, and
  FastISel won't run properly if those places don't do the right thing.
- Test looks for normal ISel versus FastISel behavior, and not
  something more subtle that doesn't work everywhere.

Based on work by Andrea Di Biagio.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195491 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-22 19:11:24 +00:00

43 lines
885 B
LLVM

; RUN: llc -O2 -march=x86 < %s | FileCheck %s
define i32* @fooOptnone(i32* %p, i32* %q, i32** %z) #0 {
entry:
%r = load i32* %p
%s = load i32* %q
%y = load i32** %z
%t0 = add i32 %r, %s
%t1 = add i32 %t0, 1
%t2 = getelementptr i32* %y, i32 1
%t3 = getelementptr i32* %t2, i32 %t1
ret i32* %t3
; 'optnone' should use fast-isel which will not produce 'lea'.
; CHECK-LABEL: fooOptnone:
; CHECK-NOT: lea
; CHECK: ret
}
define i32* @fooNormal(i32* %p, i32* %q, i32** %z) #1 {
entry:
%r = load i32* %p
%s = load i32* %q
%y = load i32** %z
%t0 = add i32 %r, %s
%t1 = add i32 %t0, 1
%t2 = getelementptr i32* %y, i32 1
%t3 = getelementptr i32* %t2, i32 %t1
ret i32* %t3
; Normal ISel will produce 'lea'.
; CHECK-LABEL: fooNormal:
; CHECK: lea
; CHECK: ret
}
attributes #0 = { nounwind optnone noinline }
attributes #1 = { nounwind }