test/Transforms/InstCombine/CPP_min_max.ll

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

; This testcase corresponds to PR362, which notices that this horrible code
; is generated by the C++ front-end and LLVM optimizers, which has lots of
; loads and other stuff that are unneeded.
;
; Instcombine should propagate the load through the select instructions to
; allow elimination of the extra stuff by the mem2reg pass.

define void @_Z5test1RiS_(ptr %x, ptr %y) {
; CHECK-LABEL: @_Z5test1RiS_(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[TMP_1_I:%.*]] = load i32, ptr [[Y:%.*]], align 4
; CHECK-NEXT:    [[TMP_3_I:%.*]] = load i32, ptr [[X:%.*]], align 4
; CHECK-NEXT:    [[TMP_4:%.*]] = call i32 @llvm.smin.i32(i32 [[TMP_1_I]], i32 [[TMP_3_I]])
; CHECK-NEXT:    store i32 [[TMP_4]], ptr [[X]], align 4
; CHECK-NEXT:    ret void
;
entry:
  %tmp.1.i = load i32, ptr %y         ; <i32> [#uses=1]
  %tmp.3.i = load i32, ptr %x         ; <i32> [#uses=1]
  %tmp.4.i = icmp slt i32 %tmp.1.i, %tmp.3.i              ; <i1> [#uses=1]
  %retval.i = select i1 %tmp.4.i, ptr %y, ptr %x                ; <ptr> [#uses=1]
  %tmp.4 = load i32, ptr %retval.i            ; <i32> [#uses=1]
  store i32 %tmp.4, ptr %x
  ret void
}

define void @_Z5test2RiS_(ptr %x, ptr %y) {
; CHECK-LABEL: @_Z5test2RiS_(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[TMP_2:%.*]] = load i32, ptr [[X:%.*]], align 4
; CHECK-NEXT:    [[TMP_3_I:%.*]] = load i32, ptr [[Y:%.*]], align 4
; CHECK-NEXT:    [[TMP_6:%.*]] = call i32 @llvm.smax.i32(i32 [[TMP_2]], i32 [[TMP_3_I]])
; CHECK-NEXT:    store i32 [[TMP_6]], ptr [[Y]], align 4
; CHECK-NEXT:    ret void
;
entry:
  %tmp.0 = alloca i32             ; <ptr> [#uses=2]
  %tmp.2 = load i32, ptr %x           ; <i32> [#uses=2]
  store i32 %tmp.2, ptr %tmp.0
  %tmp.3.i = load i32, ptr %y         ; <i32> [#uses=1]
  %tmp.4.i = icmp slt i32 %tmp.2, %tmp.3.i                ; <i1> [#uses=1]
  %retval.i = select i1 %tmp.4.i, ptr %y, ptr %tmp.0            ; <ptr> [#uses=1]
  %tmp.6 = load i32, ptr %retval.i            ; <i32> [#uses=1]
  store i32 %tmp.6, ptr %y
  ret void
}