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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
; RUN: llc -mtriple=x86_64-pc-win32 -mattr=+cmov %s -o - | FileCheck %s --check-prefix=CHECKWIN64
define i32 @one32_nooptsize() {
entry:
ret i32 1
; When not optimizing for size, use mov.
; CHECK32-LABEL: one32_nooptsize:
; CHECK32: movl $1, %eax
; CHECK32-NEXT: retl
; CHECK64-LABEL: one32_nooptsize:
; CHECK64: movl $1, %eax
; CHECK64-NEXT: retq
}
define i32 @one32() optsize {
entry:
ret i32 1
; CHECK32-LABEL: one32:
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: incl %eax
; CHECK32-NEXT: retl
; FIXME: Figure out the best approach in 64-bit mode.
; CHECK64-LABEL: one32:
; CHECK64: movl $1, %eax
; CHECK64-NEXT: retq
}
define i32 @one32_minsize() minsize {
entry:
ret i32 1
; On 32-bit, xor-inc is preferred over push-pop.
; CHECK32-LABEL: one32_minsize:
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: incl %eax
; CHECK32-NEXT: retl
; On 64-bit we don't do xor-inc yet, so push-pop it is. Note that we have to
; pop into a 64-bit register even when we just need 32 bits.
; CHECK64-LABEL: one32_minsize:
; CHECK64: pushq $1
; CHECK64: .cfi_adjust_cfa_offset 8
; CHECK64: popq %rax
; CHECK64: .cfi_adjust_cfa_offset -8
; CHECK64-NEXT: retq
; On Win64 we can't adjust the stack unless there's a frame pointer.
; CHECKWIN64-LABEL: one32_minsize:
; CHECKWIN64: movl $1, %eax
; CHECKWIN64-NEXT: retq
}
define i32 @pr26023() minsize {
entry:
%x = alloca [120 x i8]
%0 = getelementptr inbounds [120 x i8], [120 x i8]* %x, i64 0, i64 0
call void asm sideeffect "", "imr,~{memory},~{dirflag},~{fpsr},~{flags}"(i8* %0)
%arrayidx = getelementptr inbounds [120 x i8], [120 x i8]* %x, i64 0, i64 119
store volatile i8 -2, i8* %arrayidx
call void asm sideeffect "", "r,~{dirflag},~{fpsr},~{flags}"(i32 5)
%1 = load volatile i8, i8* %arrayidx
%conv = sext i8 %1 to i32
ret i32 %conv
; The function writes to the redzone, so push/pop cannot be used.
; CHECK64-LABEL: pr26023:
; CHECK64: movl $5, %ecx
; CHECK64: retq
; 32-bit X86 doesn't have a redzone.
; CHECK32-LABEL: pr26023:
; CHECK32: pushl $5
; CHECK32: popl %ecx
; CHECK32: retl
}
define i64 @one64_minsize() minsize {
entry:
ret i64 1
; On 64-bit we don't do xor-inc yet, so push-pop it is.
; CHECK64-LABEL: one64_minsize:
; CHECK64: pushq $1
; CHECK64: .cfi_adjust_cfa_offset 8
; CHECK64: popq %rax
; CHECK64: .cfi_adjust_cfa_offset -8
; CHECK64-NEXT: retq
; On Win64 we can't adjust the stack unless there's a frame pointer.
; CHECKWIN64-LABEL: one64_minsize:
; CHECKWIN64: movl $1, %eax
; CHECKWIN64-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: retl
}
define i32 @minus_one32_minsize() minsize {
entry:
ret i32 -1
; xor-dec is preferred over push-pop.
; CHECK32-LABEL: minus_one32_minsize:
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: decl %eax
; CHECK32-NEXT: retl
}
define i16 @one16() optsize {
entry:
ret i16 1
; CHECK32-LABEL: one16:
; CHECK32: xorl %eax, %eax
; CHECK32-NEXT: incl %eax
; CHECK32-NEXT: # kill
; 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: # kill
; CHECK32-NEXT: retl
}
define i32 @minus_five32() minsize {
entry:
ret i32 -5
; CHECK32-LABEL: minus_five32:
; CHECK32: pushl $-5
; CHECK32: popl %eax
; CHECK32: retl
}
define i64 @minus_five64() minsize {
entry:
ret i64 -5
; CHECK64-LABEL: minus_five64:
; CHECK64: pushq $-5
; CHECK64: .cfi_adjust_cfa_offset 8
; CHECK64: popq %rax
; CHECK64: .cfi_adjust_cfa_offset -8
; CHECK64: retq
}
define i32 @rematerialize_minus_one() 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: rematerialize_minus_one
; 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 @rematerialize_minus_one_eflags(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: rematerialize_minus_one_eflags
; 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)
|