llvm-project/llvm/test/CodeGen/X86/twoaddr-lea.ll

25 lines
874 B
LLVM
Raw Normal View History

;; X's live range extends beyond the shift, so the register allocator
;; cannot coalesce 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: llc < %s -march=x86 -x86-asm-syntax=intel | \
; RUN: not grep {mov E.X, E.X}
@G = external global i32 ; <i32*> [#uses=3]
define i32 @test1(i32 %X, i32 %Y) {
%Z = add i32 %X, %Y ; <i32> [#uses=1]
volatile store i32 %Y, i32* @G
volatile store i32 %Z, i32* @G
ret i32 %X
}
define i32 @test2(i32 %X) {
%Z = add i32 %X, 1 ; <i32> [#uses=1]
volatile store i32 %Z, i32* @G
ret i32 %X
}