xref: /aosp_15_r20/external/llvm/test/Transforms/SimplifyCFG/switch-masked-bits.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -simplifycfg < %s | FileCheck %s

define i32 @test1(i32 %x) nounwind {
; CHECK-LABEL: @test1(
; CHECK-NEXT:  a:
; CHECK-NEXT:    [[I:%.*]] = shl i32 %x, 1
; CHECK-NEXT:    [[COND:%.*]] = icmp eq i32 [[I]], 24
; CHECK-NEXT:    [[DOT:%.*]] = select i1 [[COND]], i32 5, i32 0
; CHECK-NEXT:    ret i32 [[DOT]]
;
  %i = shl i32 %x, 1
  switch i32 %i, label %a [
  i32 21, label %b
  i32 24, label %c
  ]

a:
  ret i32 0
b:
  ret i32 3
c:
  ret i32 5
}


define i32 @test2(i32 %x) nounwind {
; CHECK-LABEL: @test2(
; CHECK-NEXT:  a:
; CHECK-NEXT:    ret i32 0
;
  %i = shl i32 %x, 1
  switch i32 %i, label %a [
  i32 21, label %b
  i32 23, label %c
  ]

a:
  ret i32 0
b:
  ret i32 3
c:
  ret i32 5
}

; We're sign extending an 8-bit value.
; The switch condition must be in the range [-128, 127], so any cases outside of that range must be dead.

define i1 @repeated_signbits(i8 %condition) {
; CHECK-LABEL: @repeated_signbits(
; CHECK:         switch i32
; CHECK-DAG:     i32 -128, label %a
; CHECK-DAG:     i32 -1, label %a
; CHECK-DAG:     i32  0, label %a
; CHECK-DAG:     i32  127, label %a
; CHECK-NEXT:    ]
;
entry:
  %sext = sext i8 %condition to i32
  switch i32 %sext, label %default [
  i32 -2147483648, label %a
  i32 -129, label %a
  i32 -128, label %a
  i32 -1, label %a
  i32  0, label %a
  i32  127, label %a
  i32  128, label %a
  i32  2147483647, label %a
  ]

a:
  ret i1 1

default:
  ret i1 0
}