test/Transforms/SCCP/sccptest.ll

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

; This is a basic correctness check for constant propagation.  The add
; instruction should be eliminated.

define i32 @test1(i1 %B) {
; CHECK-LABEL: @test1(
; CHECK-NEXT:    br i1 [[B:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK:       BB1:
; CHECK-NEXT:    br label [[BB3:%.*]]
; CHECK:       BB2:
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       BB3:
; CHECK-NEXT:    [[RET:%.*]] = phi i32 [ 0, [[BB1]] ], [ 1, [[BB2]] ]
; CHECK-NEXT:    ret i32 [[RET]]
;
  br i1 %B, label %BB1, label %BB2
BB1:		; preds = %0
  %Val = add i32 0, 0		; <i32> [#uses=1]
  br label %BB3
BB2:		; preds = %0
  br label %BB3
BB3:		; preds = %BB2, %BB1
  %Ret = phi i32 [ %Val, %BB1 ], [ 1, %BB2 ]		; <i32> [#uses=1]
  ret i32 %Ret

}

; This is the test case taken from appel's book that illustrates a hard case
; that SCCP gets right.
;
define i32 @test2(i32 %i0, i32 %j0) {
; CHECK-LABEL: @test2(
; CHECK-NEXT:  BB1:
; CHECK-NEXT:    br label [[BB2:%.*]]
; CHECK:       BB2:
; CHECK-NEXT:    [[K2:%.*]] = phi i32 [ [[K3:%.*]], [[BB7:%.*]] ], [ 0, [[BB1:%.*]] ]
; CHECK-NEXT:    [[KCOND:%.*]] = icmp slt i32 [[K2]], 100
; CHECK-NEXT:    br i1 [[KCOND]], label [[BB3:%.*]], label [[BB4:%.*]]
; CHECK:       BB3:
; CHECK-NEXT:    br label [[BB5:%.*]]
; CHECK:       BB4:
; CHECK-NEXT:    ret i32 1
; CHECK:       BB5:
; CHECK-NEXT:    [[K3]] = add i32 [[K2]], 1
; CHECK-NEXT:    br label [[BB7]]
; CHECK:       BB7:
; CHECK-NEXT:    br label [[BB2]]
;
BB1:
  br label %BB2
BB2:
  %j2 = phi i32 [ %j4, %BB7 ], [ 1, %BB1 ]
  %k2 = phi i32 [ %k4, %BB7 ], [ 0, %BB1 ]
  %kcond = icmp slt i32 %k2, 100
  br i1 %kcond, label %BB3, label %BB4
BB3:
  %jcond = icmp slt i32 %j2, 20
  br i1 %jcond, label %BB5, label %BB6
BB4:
  ret i32 %j2
BB5:
  %k3 = add i32 %k2, 1
  br label %BB7
BB6:
  %k5 = add i32 %k2, 1
  br label %BB7
BB7:
  %j4 = phi i32 [ 1, %BB5 ], [ %k2, %BB6 ]
  %k4 = phi i32 [ %k3, %BB5 ], [ %k5, %BB6 ]
  br label %BB2
}