add support for PHI nodes to ObjectSizeOffsetVisitor
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171298 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp
index cfd8fcf..2503bfa 100644
--- a/lib/Analysis/MemoryBuiltins.cpp
+++ b/lib/Analysis/MemoryBuiltins.cpp
@@ -535,9 +535,20 @@
return unknown();
}
-SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode&) {
- // too complex to analyze statically.
- return unknown();
+SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PHI) {
+ if (PHI.getNumIncomingValues() == 0)
+ return unknown();
+
+ SizeOffsetType Ret = compute(PHI.getIncomingValue(0));
+ if (!bothKnown(Ret))
+ return unknown();
+
+ // verify that all PHI incoming pointers have the same size and offset
+ for (unsigned i = 1, e = PHI.getNumIncomingValues(); i != e; ++i) {
+ if (compute(PHI.getIncomingValue(i)) != Ret)
+ return unknown();
+ }
+ return Ret;
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
diff --git a/test/Transforms/InstCombine/objsize.ll b/test/Transforms/InstCombine/objsize.ll
index 31a3cb4..de8ac97 100644
--- a/test/Transforms/InstCombine/objsize.ll
+++ b/test/Transforms/InstCombine/objsize.ll
@@ -256,3 +256,57 @@
return:
ret i32 7
}
+
+declare noalias i8* @valloc(i32) nounwind
+
+; CHECK: @test14
+; CHECK: ret i32 6
+define i32 @test14(i32 %a) nounwind {
+ switch i32 %a, label %sw.default [
+ i32 1, label %sw.bb
+ i32 2, label %sw.bb1
+ ]
+
+sw.bb:
+ %call = tail call noalias i8* @malloc(i32 6) nounwind
+ br label %sw.epilog
+
+sw.bb1:
+ %call2 = tail call noalias i8* @calloc(i32 3, i32 2) nounwind
+ br label %sw.epilog
+
+sw.default:
+ %call3 = tail call noalias i8* @valloc(i32 6) nounwind
+ br label %sw.epilog
+
+sw.epilog:
+ %b.0 = phi i8* [ %call3, %sw.default ], [ %call2, %sw.bb1 ], [ %call, %sw.bb ]
+ %1 = tail call i32 @llvm.objectsize.i32(i8* %b.0, i1 false)
+ ret i32 %1
+}
+
+; CHECK: @test15
+; CHECK: llvm.objectsize
+define i32 @test15(i32 %a) nounwind {
+ switch i32 %a, label %sw.default [
+ i32 1, label %sw.bb
+ i32 2, label %sw.bb1
+ ]
+
+sw.bb:
+ %call = tail call noalias i8* @malloc(i32 3) nounwind
+ br label %sw.epilog
+
+sw.bb1:
+ %call2 = tail call noalias i8* @calloc(i32 2, i32 1) nounwind
+ br label %sw.epilog
+
+sw.default:
+ %call3 = tail call noalias i8* @valloc(i32 3) nounwind
+ br label %sw.epilog
+
+sw.epilog:
+ %b.0 = phi i8* [ %call3, %sw.default ], [ %call2, %sw.bb1 ], [ %call, %sw.bb ]
+ %1 = tail call i32 @llvm.objectsize.i32(i8* %b.0, i1 false)
+ ret i32 %1
+}