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; RUN: llc -mtriple=i686-unknown-linux-gnu -mattr=+cmov %s -o - | FileCheck %s --check-prefix=CHECK32
; RUN: llc -mtriple=x86_64-unknown-linux-gnu -mattr=+cmov %s -o - | FileCheck %s --check-prefix=CHECK64
define i32 @one32() optsize {
entry:
ret i32 1
; CHECK32-LABEL: one32
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: incl %eax
; CHECK32-NEXT: ret
; FIXME: Figure out the best approach in 64-bit mode.
; CHECK64-LABEL: one32
; CHECK64: movl $1, %eax
; CHECK64-NEXT: retq
}
define i32 @minus_one32() optsize {
entry:
ret i32 -1
; CHECK32-LABEL: minus_one32
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: decl %eax
; CHECK32-NEXT: ret
}
define i16 @one16() optsize {
entry:
ret i16 1
; CHECK32-LABEL: one16
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: incl %eax
; CHECK32-NEXT: retl
}
define i16 @minus_one16() optsize {
entry:
ret i16 -1
; CHECK32-LABEL: minus_one16
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: decl %eax
; CHECK32-NEXT: retl
}
define i32 @test_rematerialization() optsize {
entry:
; Materialize -1 (thiscall forces it into %ecx).
tail call x86_thiscallcc void @f(i32 -1)
; Clobber all registers except %esp, leaving nowhere to store the -1 besides
; spilling it to the stack.
tail call void asm sideeffect "", "~{eax},~{ebx},~{ecx},~{edx},~{edi},~{esi},~{ebp},~{dirflag},~{fpsr},~{flags}"()
; -1 should be re-materialized here instead of getting spilled above.
ret i32 -1
; CHECK32-LABEL: test_rematerialization
; CHECK32: xorl %ecx, %ecx
; CHECK32-NEXT: decl %ecx
; CHECK32: calll
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: decl %eax
; CHECK32-NOT: %eax
; CHECK32: retl
}
define i32 @test_rematerialization2(i32 %x) optsize {
entry:
; Materialize -1 (thiscall forces it into %ecx).
tail call x86_thiscallcc void @f(i32 -1)
; Clobber all registers except %esp, leaving nowhere to store the -1 besides
; spilling it to the stack.
tail call void asm sideeffect "", "~{eax},~{ebx},~{ecx},~{edx},~{edi},~{esi},~{ebp},~{dirflag},~{fpsr},~{flags}"()
; Define eflags.
%a = icmp ne i32 %x, 123
%b = zext i1 %a to i32
; Cause -1 to be rematerialized right in front of the cmov, which needs eflags.
; It must therefore not use the xor-dec lowering.
%c = select i1 %a, i32 %b, i32 -1
ret i32 %c
; CHECK32-LABEL: test_rematerialization2
; CHECK32: xorl %ecx, %ecx
; CHECK32-NEXT: decl %ecx
; CHECK32: calll
; CHECK32: cmpl
; CHECK32: setne
; CHECK32-NOT: xorl
; CHECK32: movl $-1
; CHECK32: cmov
; CHECK32: retl
}
declare x86_thiscallcc void @f(i32)
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