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; RUN: llc < %s -mtriple=aarch64-unknown-unknown | FileCheck %s
; Compare if negative and select of constants where one constant is zero.
define i32 @neg_sel_constants(i32 %a) {
; CHECK-LABEL: neg_sel_constants:
; CHECK: // BB#0:
; CHECK-NEXT: mov w8, #5
; CHECK-NEXT: and w0, w8, w0, asr #31
; CHECK-NEXT: ret
;
%tmp.1 = icmp slt i32 %a, 0
%retval = select i1 %tmp.1, i32 5, i32 0
ret i32 %retval
}
; Compare if negative and select of constants where one constant is zero and the other is a single bit.
define i32 @neg_sel_special_constant(i32 %a) {
; CHECK-LABEL: neg_sel_special_constant:
; CHECK: // BB#0:
; CHECK-NEXT: lsr w8, w0, #22
; CHECK-NEXT: and w0, w8, #0x200
; CHECK-NEXT: ret
;
%tmp.1 = icmp slt i32 %a, 0
%retval = select i1 %tmp.1, i32 512, i32 0
ret i32 %retval
}
; Compare if negative and select variable or zero.
define i32 @neg_sel_variable_and_zero(i32 %a, i32 %b) {
; CHECK-LABEL: neg_sel_variable_and_zero:
; CHECK: // BB#0:
; CHECK-NEXT: and w0, w1, w0, asr #31
; CHECK-NEXT: ret
;
%tmp.1 = icmp slt i32 %a, 0
%retval = select i1 %tmp.1, i32 %b, i32 0
ret i32 %retval
}
; Compare if not positive and select the same variable as being compared: smin(a, 0).
define i32 @not_pos_sel_same_variable(i32 %a) {
; CHECK-LABEL: not_pos_sel_same_variable:
; CHECK: // BB#0:
; CHECK-NEXT: and w0, w0, w0, asr #31
; CHECK-NEXT: ret
;
%tmp = icmp slt i32 %a, 1
%min = select i1 %tmp, i32 %a, i32 0
ret i32 %min
}
; FIXME: Flipping the comparison condition can be handled by getting the bitwise not of the sign mask.
; Compare if positive and select of constants where one constant is zero.
define i32 @pos_sel_constants(i32 %a) {
; CHECK-LABEL: pos_sel_constants:
; CHECK: // BB#0:
; CHECK-NEXT: cmp w0, #0
; CHECK-NEXT: mov w8, #5
; CHECK-NEXT: csel w0, w8, wzr, ge
; CHECK-NEXT: ret
;
%tmp.1 = icmp sgt i32 %a, -1
%retval = select i1 %tmp.1, i32 5, i32 0
ret i32 %retval
}
; Compare if positive and select of constants where one constant is zero and the other is a single bit.
define i32 @pos_sel_special_constant(i32 %a) {
; CHECK-LABEL: pos_sel_special_constant:
; CHECK: // BB#0:
; CHECK-NEXT: cmp w0, #0
; CHECK-NEXT: cset w8, ge
; CHECK-NEXT: lsl w0, w8, #9
; CHECK-NEXT: ret
;
%tmp.1 = icmp sgt i32 %a, -1
%retval = select i1 %tmp.1, i32 512, i32 0
ret i32 %retval
}
; Compare if positive and select variable or zero.
define i32 @pos_sel_variable_and_zero(i32 %a, i32 %b) {
; CHECK-LABEL: pos_sel_variable_and_zero:
; CHECK: // BB#0:
; CHECK-NEXT: cmp w0, #0
; CHECK-NEXT: csel w0, w1, wzr, ge
; CHECK-NEXT: ret
;
%tmp.1 = icmp sgt i32 %a, -1
%retval = select i1 %tmp.1, i32 %b, i32 0
ret i32 %retval
}
; Compare if not negative or zero and select the same variable as being compared: smax(a, 0).
define i32 @not_neg_sel_same_variable(i32 %a) {
; CHECK-LABEL: not_neg_sel_same_variable:
; CHECK: // BB#0:
; CHECK-NEXT: cmp w0, #0
; CHECK-NEXT: csel w0, w0, wzr, gt
; CHECK-NEXT: ret
;
%tmp = icmp sgt i32 %a, 0
%min = select i1 %tmp, i32 %a, i32 0
ret i32 %min
}
; https://llvm.org/bugs/show_bug.cgi?id=31175
; ret = (x-y) > 0 ? x-y : 0
define i32 @PR31175(i32 %x, i32 %y) {
; CHECK-LABEL: PR31175:
; CHECK: // BB#0:
; CHECK-NEXT: sub w8, w0, w1
; CHECK-NEXT: cmp w8, #0
; CHECK-NEXT: csel w0, w8, wzr, gt
; CHECK-NEXT: ret
;
%sub = sub nsw i32 %x, %y
%cmp = icmp sgt i32 %sub, 0
%sel = select i1 %cmp, i32 %sub, i32 0
ret i32 %sel
}
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