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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
; RUN: llc -mtriple=riscv64 -mattr=+zicond < %s | FileCheck %s --check-prefixes=CHECK,CHEAP
; RUN: llc -mtriple=riscv64 -mattr=+zicond,+predictable-select-expensive < %s | FileCheck %s --check-prefixes=CHECK,EXPENSIVE
; Test has not predictable select, which should not be transformed to a branch
define i32 @test1(i32 %a) {
; CHECK-LABEL: test1:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: sext.w a1, a0
; CHECK-NEXT: slti a1, a1, 1
; CHECK-NEXT: addiw a0, a0, -1
; CHECK-NEXT: czero.nez a0, a0, a1
; CHECK-NEXT: ret
entry:
%cmp = icmp slt i32 %a, 1
%dec = sub i32 %a, 1
%res = select i1 %cmp, i32 0, i32 %dec, !prof !0
ret i32 %res
}
; Test has highly predictable select according to profile data,
; which should be transformed to a branch on cores with enabled TunePredictableSelectIsExpensive
define i32 @test2(i32 %a) {
; CHEAP-LABEL: test2:
; CHEAP: # %bb.0: # %entry
; CHEAP-NEXT: sext.w a1, a0
; CHEAP-NEXT: slti a1, a1, 1
; CHEAP-NEXT: addiw a0, a0, -1
; CHEAP-NEXT: czero.nez a0, a0, a1
; CHEAP-NEXT: ret
;
; EXPENSIVE-LABEL: test2:
; EXPENSIVE: # %bb.0: # %entry
; EXPENSIVE-NEXT: sext.w a1, a0
; EXPENSIVE-NEXT: blez a1, .LBB1_2
; EXPENSIVE-NEXT: # %bb.1: # %select.false
; EXPENSIVE-NEXT: addiw a0, a0, -1
; EXPENSIVE-NEXT: ret
; EXPENSIVE-NEXT: .LBB1_2:
; EXPENSIVE-NEXT: li a0, 0
; EXPENSIVE-NEXT: ret
entry:
%cmp = icmp slt i32 %a, 1
%dec = sub i32 %a, 1
%res = select i1 %cmp, i32 0, i32 %dec, !prof !1
ret i32 %res
}
!0 = !{!"branch_weights", i32 1, i32 1}
!1 = !{!"branch_weights", i32 1, i32 1000}
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