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; RUN: llc -O0 -mtriple=x86_64-apple-darwin %s -o - | FileCheck %s
declare void @foo(i32, ...)
declare i32 @__gxx_personality_v0(...)
; We were running out of registers for this invoke, because:
; 1. The lshr/and pattern gets matched to a no-REX MOV so that ah/bh/... can
; be used instead, cutting available registers for %b.arg down to eax, ebx,
; ecx, edx, esi, edi.
; 2. We have a base pointer taking ebx out of contention.
; 3. The landingpad block convinced us we should be defining rax here.
; 3. The al fiddling for the varargs call only noted down that al was spillable,
; not ah or hax.
;
; So by the time we need to allocate a register for the call all registers are
; tied up and unspillable.
; CHECK-LABEL: bar:
; CHECK: xorl %edi, %edi
; CHECK: movb %dil, {{[0-9]+}}(%rbx)
; CHECK: movb {{[0-9]+}}(%rbx), %al
define i32 @bar(i32 %a, i32 %b, i32 %c, i32 %d, ...) personality ptr @__gxx_personality_v0 {
%mem = alloca i32, i32 %a, align 32 ; Force rbx to be used as a base pointer
%b.tmp = lshr i32 %b, 8
%b.arg = and i32 %b.tmp, 255
invoke void(i32, ...) @foo(i32 42, ptr %mem, i32 %c, i32 %d, i32 %b.arg) to label %success unwind label %fail
success:
ret i32 0
fail:
%exc = landingpad { ptr, i32 } cleanup
%res = extractvalue { ptr, i32 } %exc, 1
ret i32 %res
}
; CHECK-LABEL: live:
; CHECK: movl {{%.*}}, %eax
define i32 @live(i32 %a, i32 %b, i32 %c, i32 %d, ...) personality ptr @__gxx_personality_v0 {
%mem = alloca i32, i32 %a, align 32 ; Force rbx to be used as a base pointer
%b.tmp = lshr i32 %b, 8
%b.arg = and i32 %b.tmp, 255
invoke void(i32, ...) @foo(i32 42) to label %success unwind label %fail
success:
ret i32 0
fail:
%exc = landingpad { ptr, i32 } cleanup
%res = extractvalue { ptr, i32 } %exc, 1
ret i32 %b.arg
}
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