From: Evan Cheng <evan.cheng@apple.com>
Date: Thu, 5 Mar 2009 06:31:26 +0000 (+0000)
Subject: Do not split edges to EH landing pads. It will cause code size explosion.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6fb8f421eef59c454dba3688aade34ca1401dff2;p=oota-llvm.git

Do not split edges to EH landing pads. It will cause code size explosion.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66140 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 1f3a13cc9ce..85e57661c15 100644
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -327,6 +327,12 @@ static void SplitEdgeNicely(TerminatorInst *TI, unsigned SuccNum,
   assert(isa<PHINode>(Dest->begin()) &&
          "This should only be called if Dest has a PHI!");
 
+  // Do not split edges to EH landing pads.
+  if (InvokeInst *Invoke = dyn_cast<InvokeInst>(TI)) {
+    if (Invoke->getSuccessor(1) == Dest)
+      return;
+  }
+
   // As a hack, never split backedges of loops.  Even though the copy for any
   // PHIs inserted on the backedge would be dead for exits from the loop, we
   // assume that the cost of *splitting* the backedge would be too high.
diff --git a/test/CodeGen/X86/split-eh-lpad-edges.ll b/test/CodeGen/X86/split-eh-lpad-edges.ll
new file mode 100644
index 00000000000..281ee7782da
--- /dev/null
+++ b/test/CodeGen/X86/split-eh-lpad-edges.ll
@@ -0,0 +1,34 @@
+; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin | not grep jmp
+; rdar://6647639
+
+	%struct.FetchPlanHeader = type { i8*, i8*, i32, i8*, i8*, i8*, i8*, i8*, %struct.NSObject* (%struct.NSObject*, %struct.objc_selector*, ...)*, %struct.__attributeDescriptionFlags }
+	%struct.NSArray = type { %struct.NSObject }
+	%struct.NSAutoreleasePool = type { %struct.NSObject, i8*, i8*, i8*, i8* }
+	%struct.NSObject = type { %struct.NSObject* }
+	%struct.__attributeDescriptionFlags = type <{ i32 }>
+	%struct._message_ref_t = type { %struct.NSObject* (%struct.NSObject*, %struct._message_ref_t*, ...)*, %struct.objc_selector* }
+	%struct.objc_selector = type opaque
+@"\01l_objc_msgSend_fixup_alloc" = external global %struct._message_ref_t, align 16		; <%struct._message_ref_t*> [#uses=2]
+
+define %struct.NSArray* @newFetchedRowsForFetchPlan_MT(%struct.FetchPlanHeader* %fetchPlan, %struct.objc_selector* %selectionMethod, %struct.NSObject* %selectionParameter) ssp {
+entry:
+	%0 = invoke %struct.NSObject* null(%struct.NSObject* null, %struct._message_ref_t* @"\01l_objc_msgSend_fixup_alloc")
+			to label %invcont unwind label %lpad		; <%struct.NSObject*> [#uses=1]
+
+invcont:		; preds = %entry
+	%1 = invoke %struct.NSObject* (%struct.NSObject*, %struct.objc_selector*, ...)* @objc_msgSend(%struct.NSObject* %0, %struct.objc_selector* null)
+			to label %invcont26 unwind label %lpad		; <%struct.NSObject*> [#uses=0]
+
+invcont26:		; preds = %invcont
+	%2 = invoke %struct.NSObject* null(%struct.NSObject* null, %struct._message_ref_t* @"\01l_objc_msgSend_fixup_alloc")
+			to label %invcont27 unwind label %lpad		; <%struct.NSObject*> [#uses=0]
+
+invcont27:		; preds = %invcont26
+	unreachable
+
+lpad:		; preds = %invcont26, %invcont, %entry
+	%pool.1 = phi %struct.NSAutoreleasePool* [ null, %entry ], [ null, %invcont ], [ null, %invcont26 ]		; <%struct.NSAutoreleasePool*> [#uses=0]
+	unreachable
+}
+
+declare %struct.NSObject* @objc_msgSend(%struct.NSObject*, %struct.objc_selector*, ...)