OSDN Git Service

[ObjCARC] Handle ARCInstKind::ClaimRV in OptimizeIndividualCalls.
authorFrederic Riss <friss@apple.com>
Wed, 17 Feb 2016 18:51:27 +0000 (18:51 +0000)
committerFrederic Riss <friss@apple.com>
Wed, 17 Feb 2016 18:51:27 +0000 (18:51 +0000)
When support for objc_unsafeClaimAutoreleasedReturnValue has been added to the
ARC optimizer in r258970, one case was missed which would lead the optimizer
to execute an llvm_unreachable. In this case, just handle ClaimRV in the same
way we handle RetainRV.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261134 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/ObjCARC/ObjCARCOpts.cpp
test/Transforms/ObjCARC/unsafe-claim-rv.ll [new file with mode: 0644]

index f0ee6e2..39e99a0 100644 (file)
@@ -889,6 +889,7 @@ void ObjCARCOpt::OptimizeIndividualCalls(Function &F) {
                            Inst->getParent(), Inst,
                            DependingInstructions, Visited, PA);
           break;
+        case ARCInstKind::ClaimRV:
         case ARCInstKind::RetainRV:
         case ARCInstKind::AutoreleaseRV:
           // Don't move these; the RV optimization depends on the autoreleaseRV
diff --git a/test/Transforms/ObjCARC/unsafe-claim-rv.ll b/test/Transforms/ObjCARC/unsafe-claim-rv.ll
new file mode 100644 (file)
index 0000000..addd0c8
--- /dev/null
@@ -0,0 +1,47 @@
+; RUN: opt -objc-arc -S < %s | FileCheck %s
+
+; Generated by compiling:
+;
+; id baz(void *X) { return (__bridge_transfer id)X; }
+; 
+; void foo(id X) {
+; void *Y = 0;
+; if (X)
+;   Y = (__bridge_retained void *)X;
+; baz(Y);
+; }
+;
+; clang -x objective-c -mllvm -enable-objc-arc-opts=0 -fobjc-arc -S -emit-llvm test.m
+;
+; And then hand-reduced further. 
+
+declare i8* @objc_autoreleaseReturnValue(i8*)
+declare i8* @objc_unsafeClaimAutoreleasedReturnValue(i8*)
+declare i8* @objc_retain(i8*)
+declare void @objc_release(i8*)
+
+define void @foo(i8* %X) {
+entry:
+  %0 = tail call i8* @objc_retain(i8* %X) 
+  %tobool = icmp eq i8* %0, null
+  br i1 %tobool, label %if.end, label %if.then
+
+if.then:                                          ; preds = %entry
+  %1 = tail call i8* @objc_retain(i8* nonnull %0)
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  %Y.0 = phi i8* [ %1, %if.then ], [ null, %entry ]
+  %2 = tail call i8* @objc_autoreleaseReturnValue(i8* %Y.0)
+  %3 = tail call i8* @objc_unsafeClaimAutoreleasedReturnValue(i8* %2)
+  tail call void @objc_release(i8* %0) 
+  ret void
+}
+
+; CHECK: if.then
+; CHECK: tail call i8* @objc_retain
+; CHECK-NEXT: call i8* @objc_autorelease
+; CHECK: %Y.0 = phi
+; CHECK-NEXT: tail call i8* @objc_unsafeClaimAutoreleasedReturnValue(i8* %Y.0)
+; CHECK-NEXT: tail call void @objc_release
+