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| ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mtriple=i386-linux-gnu -verify-machineinstrs %s -o - | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK32
; RUN: llc -mtriple=x86_64-linux-gnu -verify-machineinstrs %s -o - | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK64
; The peephole optimizer can elide some physical register copies such as
; EFLAGS. Make sure the flags are used directly, instead of needlessly using
; saving and restoring specific conditions.
@L = external global i32
@M = external global i8
declare i32 @bar(i64)
define i1 @plus_one() nounwind {
; CHECK32-LABEL: plus_one:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: movb M, %al
; CHECK32-NEXT: incl L
; CHECK32-NEXT: jne .LBB0_2
; CHECK32-NEXT: # %bb.1: # %entry
; CHECK32-NEXT: andb $8, %al
; CHECK32-NEXT: je .LBB0_2
; CHECK32-NEXT: # %bb.3: # %exit2
; CHECK32-NEXT: xorl %eax, %eax
; CHECK32-NEXT: retl
; CHECK32-NEXT: .LBB0_2: # %exit
; CHECK32-NEXT: movb $1, %al
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: plus_one:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: movb {{.*}}(%rip), %al
; CHECK64-NEXT: incl {{.*}}(%rip)
; CHECK64-NEXT: jne .LBB0_2
; CHECK64-NEXT: # %bb.1: # %entry
; CHECK64-NEXT: andb $8, %al
; CHECK64-NEXT: je .LBB0_2
; CHECK64-NEXT: # %bb.3: # %exit2
; CHECK64-NEXT: xorl %eax, %eax
; CHECK64-NEXT: retq
; CHECK64-NEXT: .LBB0_2: # %exit
; CHECK64-NEXT: movb $1, %al
; CHECK64-NEXT: retq
entry:
%loaded_L = load i32, i32* @L
%val = add nsw i32 %loaded_L, 1 ; N.B. will emit inc.
store i32 %val, i32* @L
%loaded_M = load i8, i8* @M
%masked = and i8 %loaded_M, 8
%M_is_true = icmp ne i8 %masked, 0
%L_is_false = icmp eq i32 %val, 0
%cond = and i1 %L_is_false, %M_is_true
br i1 %cond, label %exit2, label %exit
exit:
ret i1 true
exit2:
ret i1 false
}
define i1 @plus_forty_two() nounwind {
; CHECK32-LABEL: plus_forty_two:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: movb M, %al
; CHECK32-NEXT: addl $42, L
; CHECK32-NEXT: jne .LBB1_2
; CHECK32-NEXT: # %bb.1: # %entry
; CHECK32-NEXT: andb $8, %al
; CHECK32-NEXT: je .LBB1_2
; CHECK32-NEXT: # %bb.3: # %exit2
; CHECK32-NEXT: xorl %eax, %eax
; CHECK32-NEXT: retl
; CHECK32-NEXT: .LBB1_2: # %exit
; CHECK32-NEXT: movb $1, %al
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: plus_forty_two:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: movb {{.*}}(%rip), %al
; CHECK64-NEXT: addl $42, {{.*}}(%rip)
; CHECK64-NEXT: jne .LBB1_2
; CHECK64-NEXT: # %bb.1: # %entry
; CHECK64-NEXT: andb $8, %al
; CHECK64-NEXT: je .LBB1_2
; CHECK64-NEXT: # %bb.3: # %exit2
; CHECK64-NEXT: xorl %eax, %eax
; CHECK64-NEXT: retq
; CHECK64-NEXT: .LBB1_2: # %exit
; CHECK64-NEXT: movb $1, %al
; CHECK64-NEXT: retq
entry:
%loaded_L = load i32, i32* @L
%val = add nsw i32 %loaded_L, 42 ; N.B. won't emit inc.
store i32 %val, i32* @L
%loaded_M = load i8, i8* @M
%masked = and i8 %loaded_M, 8
%M_is_true = icmp ne i8 %masked, 0
%L_is_false = icmp eq i32 %val, 0
%cond = and i1 %L_is_false, %M_is_true
br i1 %cond, label %exit2, label %exit
exit:
ret i1 true
exit2:
ret i1 false
}
define i1 @minus_one() nounwind {
; CHECK32-LABEL: minus_one:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: movb M, %al
; CHECK32-NEXT: decl L
; CHECK32-NEXT: jne .LBB2_2
; CHECK32-NEXT: # %bb.1: # %entry
; CHECK32-NEXT: andb $8, %al
; CHECK32-NEXT: je .LBB2_2
; CHECK32-NEXT: # %bb.3: # %exit2
; CHECK32-NEXT: xorl %eax, %eax
; CHECK32-NEXT: retl
; CHECK32-NEXT: .LBB2_2: # %exit
; CHECK32-NEXT: movb $1, %al
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: minus_one:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: movb {{.*}}(%rip), %al
; CHECK64-NEXT: decl {{.*}}(%rip)
; CHECK64-NEXT: jne .LBB2_2
; CHECK64-NEXT: # %bb.1: # %entry
; CHECK64-NEXT: andb $8, %al
; CHECK64-NEXT: je .LBB2_2
; CHECK64-NEXT: # %bb.3: # %exit2
; CHECK64-NEXT: xorl %eax, %eax
; CHECK64-NEXT: retq
; CHECK64-NEXT: .LBB2_2: # %exit
; CHECK64-NEXT: movb $1, %al
; CHECK64-NEXT: retq
entry:
%loaded_L = load i32, i32* @L
%val = add nsw i32 %loaded_L, -1 ; N.B. will emit dec.
store i32 %val, i32* @L
%loaded_M = load i8, i8* @M
%masked = and i8 %loaded_M, 8
%M_is_true = icmp ne i8 %masked, 0
%L_is_false = icmp eq i32 %val, 0
%cond = and i1 %L_is_false, %M_is_true
br i1 %cond, label %exit2, label %exit
exit:
ret i1 true
exit2:
ret i1 false
}
define i1 @minus_forty_two() nounwind {
; CHECK32-LABEL: minus_forty_two:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: movb M, %al
; CHECK32-NEXT: addl $-42, L
; CHECK32-NEXT: jne .LBB3_2
; CHECK32-NEXT: # %bb.1: # %entry
; CHECK32-NEXT: andb $8, %al
; CHECK32-NEXT: je .LBB3_2
; CHECK32-NEXT: # %bb.3: # %exit2
; CHECK32-NEXT: xorl %eax, %eax
; CHECK32-NEXT: retl
; CHECK32-NEXT: .LBB3_2: # %exit
; CHECK32-NEXT: movb $1, %al
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: minus_forty_two:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: movb {{.*}}(%rip), %al
; CHECK64-NEXT: addl $-42, {{.*}}(%rip)
; CHECK64-NEXT: jne .LBB3_2
; CHECK64-NEXT: # %bb.1: # %entry
; CHECK64-NEXT: andb $8, %al
; CHECK64-NEXT: je .LBB3_2
; CHECK64-NEXT: # %bb.3: # %exit2
; CHECK64-NEXT: xorl %eax, %eax
; CHECK64-NEXT: retq
; CHECK64-NEXT: .LBB3_2: # %exit
; CHECK64-NEXT: movb $1, %al
; CHECK64-NEXT: retq
entry:
%loaded_L = load i32, i32* @L
%val = add nsw i32 %loaded_L, -42 ; N.B. won't emit dec.
store i32 %val, i32* @L
%loaded_M = load i8, i8* @M
%masked = and i8 %loaded_M, 8
%M_is_true = icmp ne i8 %masked, 0
%L_is_false = icmp eq i32 %val, 0
%cond = and i1 %L_is_false, %M_is_true
br i1 %cond, label %exit2, label %exit
exit:
ret i1 true
exit2:
ret i1 false
}
define i64 @test_intervening_call(i64* %foo, i64 %bar, i64 %baz) nounwind {
; CHECK32-LABEL: test_intervening_call:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: pushl %ebx
; CHECK32-NEXT: pushl %esi
; CHECK32-NEXT: pushl %eax
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %edx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ebx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ecx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %esi
; CHECK32-NEXT: lock cmpxchg8b (%esi)
; CHECK32-NEXT: setne %bl
; CHECK32-NEXT: subl $8, %esp
; CHECK32-NEXT: pushl %edx
; CHECK32-NEXT: pushl %eax
; CHECK32-NEXT: calll bar
; CHECK32-NEXT: addl $16, %esp
; CHECK32-NEXT: testb %bl, %bl
; CHECK32-NEXT: jne .LBB4_3
; CHECK32-NEXT: # %bb.1: # %t
; CHECK32-NEXT: movl $42, %eax
; CHECK32-NEXT: jmp .LBB4_2
; CHECK32-NEXT: .LBB4_3: # %f
; CHECK32-NEXT: xorl %eax, %eax
; CHECK32-NEXT: .LBB4_2: # %t
; CHECK32-NEXT: xorl %edx, %edx
; CHECK32-NEXT: addl $4, %esp
; CHECK32-NEXT: popl %esi
; CHECK32-NEXT: popl %ebx
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: test_intervening_call:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: pushq %rbx
; CHECK64-NEXT: movq %rsi, %rax
; CHECK64-NEXT: lock cmpxchgq %rdx, (%rdi)
; CHECK64-NEXT: setne %bl
; CHECK64-NEXT: movq %rax, %rdi
; CHECK64-NEXT: callq bar
; CHECK64-NEXT: testb %bl, %bl
; CHECK64-NEXT: jne .LBB4_2
; CHECK64-NEXT: # %bb.1: # %t
; CHECK64-NEXT: movl $42, %eax
; CHECK64-NEXT: popq %rbx
; CHECK64-NEXT: retq
; CHECK64-NEXT: .LBB4_2: # %f
; CHECK64-NEXT: xorl %eax, %eax
; CHECK64-NEXT: popq %rbx
; CHECK64-NEXT: retq
entry:
; cmpxchg sets EFLAGS, call clobbers it, then br uses EFLAGS.
%cx = cmpxchg i64* %foo, i64 %bar, i64 %baz seq_cst seq_cst
%v = extractvalue { i64, i1 } %cx, 0
%p = extractvalue { i64, i1 } %cx, 1
call i32 @bar(i64 %v)
br i1 %p, label %t, label %f
t:
ret i64 42
f:
ret i64 0
}
define i64 @test_two_live_flags(i64* %foo0, i64 %bar0, i64 %baz0, i64* %foo1, i64 %bar1, i64 %baz1) nounwind {
; CHECK32-LABEL: test_two_live_flags:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: pushl %ebp
; CHECK32-NEXT: pushl %ebx
; CHECK32-NEXT: pushl %edi
; CHECK32-NEXT: pushl %esi
; CHECK32-NEXT: pushl %eax
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %edi
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ebp
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %edx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ebx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ecx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %esi
; CHECK32-NEXT: lock cmpxchg8b (%esi)
; CHECK32-NEXT: setne {{[-0-9]+}}(%e{{[sb]}}p) # 1-byte Folded Spill
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %eax
; CHECK32-NEXT: movl %edi, %edx
; CHECK32-NEXT: movl %ebp, %ecx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ebx
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %esi
; CHECK32-NEXT: lock cmpxchg8b (%esi)
; CHECK32-NEXT: sete %al
; CHECK32-NEXT: cmpb $0, {{[-0-9]+}}(%e{{[sb]}}p) # 1-byte Folded Reload
; CHECK32-NEXT: jne .LBB5_4
; CHECK32-NEXT: # %bb.1: # %entry
; CHECK32-NEXT: testb %al, %al
; CHECK32-NEXT: je .LBB5_4
; CHECK32-NEXT: # %bb.2: # %t
; CHECK32-NEXT: movl $42, %eax
; CHECK32-NEXT: jmp .LBB5_3
; CHECK32-NEXT: .LBB5_4: # %f
; CHECK32-NEXT: xorl %eax, %eax
; CHECK32-NEXT: .LBB5_3: # %t
; CHECK32-NEXT: xorl %edx, %edx
; CHECK32-NEXT: addl $4, %esp
; CHECK32-NEXT: popl %esi
; CHECK32-NEXT: popl %edi
; CHECK32-NEXT: popl %ebx
; CHECK32-NEXT: popl %ebp
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: test_two_live_flags:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: movq %rsi, %rax
; CHECK64-NEXT: lock cmpxchgq %rdx, (%rdi)
; CHECK64-NEXT: setne %dl
; CHECK64-NEXT: movq %r8, %rax
; CHECK64-NEXT: lock cmpxchgq %r9, (%rcx)
; CHECK64-NEXT: sete %al
; CHECK64-NEXT: testb %dl, %dl
; CHECK64-NEXT: jne .LBB5_3
; CHECK64-NEXT: # %bb.1: # %entry
; CHECK64-NEXT: testb %al, %al
; CHECK64-NEXT: je .LBB5_3
; CHECK64-NEXT: # %bb.2: # %t
; CHECK64-NEXT: movl $42, %eax
; CHECK64-NEXT: retq
; CHECK64-NEXT: .LBB5_3: # %f
; CHECK64-NEXT: xorl %eax, %eax
; CHECK64-NEXT: retq
entry:
%cx0 = cmpxchg i64* %foo0, i64 %bar0, i64 %baz0 seq_cst seq_cst
%p0 = extractvalue { i64, i1 } %cx0, 1
%cx1 = cmpxchg i64* %foo1, i64 %bar1, i64 %baz1 seq_cst seq_cst
%p1 = extractvalue { i64, i1 } %cx1, 1
%flag = and i1 %p0, %p1
br i1 %flag, label %t, label %f
t:
ret i64 42
f:
ret i64 0
}
define i1 @asm_clobbering_flags(i32* %mem) nounwind {
; CHECK32-LABEL: asm_clobbering_flags:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: movl {{[0-9]+}}(%esp), %ecx
; CHECK32-NEXT: movl (%ecx), %edx
; CHECK32-NEXT: testl %edx, %edx
; CHECK32-NEXT: setg %al
; CHECK32-NEXT: #APP
; CHECK32-NEXT: bsfl %edx, %edx
; CHECK32-NEXT: #NO_APP
; CHECK32-NEXT: movl %edx, (%ecx)
; CHECK32-NEXT: retl
;
; CHECK64-LABEL: asm_clobbering_flags:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: movl (%rdi), %ecx
; CHECK64-NEXT: testl %ecx, %ecx
; CHECK64-NEXT: setg %al
; CHECK64-NEXT: #APP
; CHECK64-NEXT: bsfl %ecx, %ecx
; CHECK64-NEXT: #NO_APP
; CHECK64-NEXT: movl %ecx, (%rdi)
; CHECK64-NEXT: retq
entry:
%val = load i32, i32* %mem, align 4
%cmp = icmp sgt i32 %val, 0
%res = tail call i32 asm "bsfl $1,$0", "=r,r,~{cc},~{dirflag},~{fpsr},~{flags}"(i32 %val)
store i32 %res, i32* %mem, align 4
ret i1 %cmp
}
|