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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -basicaa -newgvn -S | FileCheck %s
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
define i1 @patatino(i8* %blah, i32 %choice) {
; CHECK-LABEL: @patatino(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[WHILE_COND:%.*]]
; CHECK: while.cond:
; CHECK-NEXT: [[FOO:%.*]] = phi i8* [ [[BLAH:%.*]], [[ENTRY:%.*]] ], [ null, [[WHILE_BODY:%.*]] ]
; CHECK-NEXT: switch i32 [[CHOICE:%.*]], label [[WHILE_BODY]] [
; CHECK-NEXT: i32 -1, label [[WHILE_END:%.*]]
; CHECK-NEXT: i32 40, label [[LAND_END:%.*]]
; CHECK-NEXT: ]
; CHECK: land.end:
; CHECK-NEXT: br label [[WHILE_END]]
; CHECK: while.body:
; CHECK-NEXT: br label [[WHILE_COND]]
; CHECK: while.end:
; CHECK-NEXT: store i8 0, i8* [[FOO]], align 1
; CHECK-NEXT: [[TMP0:%.*]] = load i8, i8* [[BLAH]], align 1
; CHECK-NEXT: [[LOADED:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: store i8 0, i8* [[BLAH]], align 1
; CHECK-NEXT: ret i1 [[LOADED]]
;
entry:
br label %while.cond
while.cond:
%foo = phi i8* [ %blah, %entry ], [ null, %while.body ]
switch i32 %choice, label %while.body [
i32 -1, label %while.end
i32 40, label %land.end
]
land.end:
br label %while.end
while.body:
br label %while.cond
while.end:
%foo.lcssa = phi i8* [ %foo, %land.end ], [ %foo, %while.cond ]
;; These two stores will initially be considered equivalent, but then proven not.
;; the second store would previously end up deciding it's equivalent to a previous
;; store, but it was really just finding an optimistic version of itself
;; in the congruence class.
store i8 0, i8* %foo.lcssa, align 1
%0 = load i8, i8* %blah, align 1
%loaded = icmp eq i8 %0, 0
store i8 0, i8* %blah, align 1
ret i1 %loaded
}
;; This is an example of a case where the memory states are equivalent solely due to unreachability,
;; but the stores are not equal.
define void @foo(i8* %arg) {
; CHECK-LABEL: @foo(
; CHECK-NEXT: bb:
; CHECK-NEXT: br label [[BB1:%.*]]
; CHECK: bb1:
; CHECK-NEXT: [[TMP:%.*]] = phi i8* [ [[ARG:%.*]], [[BB:%.*]] ], [ null, [[BB2:%.*]] ]
; CHECK-NEXT: br i1 undef, label [[BB3:%.*]], label [[BB2]]
; CHECK: bb2:
; CHECK-NEXT: br label [[BB1]]
; CHECK: bb3:
; CHECK-NEXT: store i8 0, i8* [[TMP]], !g !0
; CHECK-NEXT: br label [[BB4:%.*]]
; CHECK: bb4:
; CHECK-NEXT: br label [[BB6:%.*]]
; CHECK: bb6:
; CHECK-NEXT: br i1 undef, label [[BB9:%.*]], label [[BB7:%.*]]
; CHECK: bb7:
; CHECK-NEXT: switch i8 0, label [[BB6]] [
; CHECK-NEXT: i8 6, label [[BB8:%.*]]
; CHECK-NEXT: ]
; CHECK: bb8:
; CHECK-NEXT: store i8 undef, i8* null
; CHECK-NEXT: br label [[BB4]]
; CHECK: bb9:
; CHECK-NEXT: store i8 0, i8* [[ARG]], !g !0
; CHECK-NEXT: unreachable
;
bb:
br label %bb1
bb1: ; preds = %bb2, %bb
%tmp = phi i8* [ %arg, %bb ], [ null, %bb2 ]
br i1 undef, label %bb3, label %bb2
bb2: ; preds = %bb1
br label %bb1
bb3: ; preds = %bb1
store i8 0, i8* %tmp, !g !0
br label %bb4
bb4: ; preds = %bb8, %bb3
%tmp5 = phi i8* [ null, %bb8 ], [ %arg, %bb3 ]
br label %bb6
bb6: ; preds = %bb7, %bb4
br i1 undef, label %bb9, label %bb7
bb7: ; preds = %bb6
switch i8 0, label %bb6 [
i8 6, label %bb8
]
bb8: ; preds = %bb7
store i8 undef, i8* %tmp5, !g !0
br label %bb4
bb9: ; preds = %bb6
%tmp10 = phi i8* [ %tmp5, %bb6 ]
store i8 0, i8* %tmp10, !g !0
unreachable
}
!0 = !{}
|