llvm-6502/test/CodeGen/X86/overlap-shift.ll

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;; 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: llvm-upgrade < %s | llvm-as | llc -march=x86 -x86-asm-syntax=intel | \
; RUN: not grep {mov E.X, E.X}
%G = external global int
int %test1(int %X) {
%Z = shl int %X, ubyte 2
volatile store int %Z, int* %G
ret int %X
}