llvm/test/CodeGen/X86/overlap-shift.ll
2005-01-02 19:01:33 +00:00

21 lines
691 B
LLVM

;; X's live range extends beyond the shift, so the register allocator
;; cannot coallesce it with Y. Because of this, a copy needs to be
;; emitted before the shift to save the register value before it is
;; clobbered. However, this copy is not needed if the register
;; allocator turns the shift into an LEA. This also occurs for ADD.
; Check that the shift gets turned into an LEA.
; RUN: llvm-as < %s | llc -march=x86 -x86-asm-syntax=intel | not grep 'mov %E.X, %E.X'
; FIXME: We need live variable information about flags to do this xform safely. :(
; XFAIL: *
%G = external global int
int %test1(int %X) {
%Z = shl int %X, ubyte 2
volatile store int %Z, int* %G
ret int %X
}