Fix IPSCCP's code for deleting dead blocks to tolerate outstanding

blockaddress users. This fixes PR5569.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89483 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 42 insertions, 0 deletions

diff --git a/test/Transforms/IPConstantProp/dangling-block-address.ll b/test/Transforms/IPConstantProp/dangling-block-address.ll
new file mode 100644
index 0000000000..0489dfa796
--- /dev/null
+++ b/test/Transforms/IPConstantProp/dangling-block-address.ll
@@ -0,0 +1,42 @@
+; RUN: opt < %s -internalize -ipsccp -S | FileCheck %s
+; PR5569
+
+; IPSCCP should prove that the blocks are dead and delete them, and
+; properly handle the dangling blockaddress constants.
+
+; CHECK: @bar.l = internal constant [2 x i8*] [i8* inttoptr (i32 1 to i8*), i8* inttoptr (i32 1 to i8*)]
+
+@code = global [5 x i32] [i32 0, i32 0, i32 0, i32 0, i32 1], align 4 ; <[5 x i32]*> [#uses=0]
+@bar.l = internal constant [2 x i8*] [i8* blockaddress(@bar, %lab0), i8* blockaddress(@bar, %end)] ; <[2 x i8*]*> [#uses=1]
+
+define void @foo(i32 %x) nounwind readnone {
+entry:
+  %b = alloca i32, align 4                        ; <i32*> [#uses=1]
+  volatile store i32 -1, i32* %b
+  ret void
+}
+
+define void @bar(i32* nocapture %pc) nounwind readonly {
+entry:
+  br label %indirectgoto
+
+lab0:                                             ; preds = %indirectgoto
+  %indvar.next = add i32 %indvar, 1               ; <i32> [#uses=1]
+  br label %indirectgoto
+
+end:                                              ; preds = %indirectgoto
+  ret void
+
+indirectgoto:                                     ; preds = %lab0, %entry
+  %indvar = phi i32 [ %indvar.next, %lab0 ], [ 0, %entry ] ; <i32> [#uses=2]
+  %pc.addr.0 = getelementptr i32* %pc, i32 %indvar ; <i32*> [#uses=1]
+  %tmp1.pn = load i32* %pc.addr.0                 ; <i32> [#uses=1]
+  %indirect.goto.dest.in = getelementptr inbounds [2 x i8*]* @bar.l, i32 0, i32 %tmp1.pn ; <i8**> [#uses=1]
+  %indirect.goto.dest = load i8** %indirect.goto.dest.in ; <i8*> [#uses=1]
+  indirectbr i8* %indirect.goto.dest, [label %lab0, label %end]
+}
+
+define i32 @main() nounwind readnone {
+entry:
+  ret i32 0
+}