Fix PR3784: If the source of a phi comes from a bb ended with an invoke, make sure...

Also re-apply r66140 which was disabled as a workaround.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66976 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index b32db2e062fa8c73cd0fef336c15ab871869184a..6f3c82c70811ef3b9b3c5f430deb5dbc0a8e0c92 100644 (file)
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -31,6 +31,7 @@
 using namespace llvm;
 
 STATISTIC(NumAtomic, "Number of atomic phis lowered");
+STATISTIC(NumEH,     "Number of EH try blocks skipped");
 
 namespace {
   class VISIBILITY_HIDDEN PNE : public MachineFunctionPass {
@@ -65,6 +66,9 @@ namespace {
     ///
     void analyzePHINodes(const MachineFunction& Fn);
 
+    void WalkPassEHTryRange(MachineBasicBlock &MBB,
+                            MachineBasicBlock::iterator &I, unsigned SrcReg);
+
     typedef std::pair<const MachineBasicBlock*, unsigned> BBVRegPair;
     typedef std::map<BBVRegPair, unsigned> VRegPHIUse;
 
@@ -140,6 +144,39 @@ static bool isSourceDefinedByImplicitDef(const MachineInstr *MPhi,
   return true;
 }
 
+void PNE::WalkPassEHTryRange(MachineBasicBlock &MBB,
+                             MachineBasicBlock::iterator &I, unsigned SrcReg) {
+  if (I == MBB.begin())
+    return;
+  MachineBasicBlock::iterator PI = prior(I);
+  if (PI->getOpcode() != TargetInstrInfo::EH_LABEL)
+    return;
+
+  // Trying to walk pass the EH try range. If we run into a use instruction,
+  // we want to insert the copy there.
+  SmallPtrSet<MachineInstr*, 4> UsesInMBB;
+  for (MachineRegisterInfo::use_iterator UI = MRI->use_begin(SrcReg),
+         UE = MRI->use_end(); UI != UE; ++UI) {
+    MachineInstr *UseMI = &*UI;
+    if (UseMI->getParent() == &MBB)
+      UsesInMBB.insert(UseMI);
+  }
+
+  while (PI != MBB.begin()) {
+    --PI;
+    if (PI->getOpcode() == TargetInstrInfo::EH_LABEL) {
+      ++NumEH;
+      I = PI;
+      return;
+    } else if (UsesInMBB.count(&*PI)) {
+      ++NumEH;
+      I = next(PI);
+      return;
+    }
+  }
+  return;
+}
+
 /// LowerAtomicPHINode - Lower the PHI node at the top of the specified block,
 /// under the assuption that it needs to be lowered in a way that supports
 /// atomic execution of PHIs.  This lowering method is always correct all of the
@@ -238,6 +275,9 @@ void PNE::LowerAtomicPHINode(MachineBasicBlock &MBB,
     // in the block (or end()).
     MachineBasicBlock::iterator InsertPos = opBlock.getFirstTerminator();
 
+    // Walk pass EH try range if needed.
+    WalkPassEHTryRange(opBlock, InsertPos, SrcReg);
+
     // Insert the copy.
     TII->copyRegToReg(opBlock, InsertPos, IncomingReg, SrcReg, RC, RC);
 

diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 1f3a13cc9cec2193da4c804ba484878deefed8f3..85e57661c1545b975a9d8acb1d5548099f52d934 100644 (file)
--- 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/X86/2009-03-13-PHIElimBug.ll b/test/CodeGen/X86/2009-03-13-PHIElimBug.ll
new file mode 100644 (file)
index 0000000..ea4150c
--- /dev/null
+++ b/test/CodeGen/X86/2009-03-13-PHIElimBug.ll
@@ -0,0 +1,37 @@
+; RUN: llvm-as < %s | llc -mtriple=i386-pc-linux-gnu -stats |& grep phielim | grep {Number of EH try blocks skipped} | grep 4
+; PR3784
+
+       %struct.c38002a__arr___XUB = type { i32, i32 }
+       %struct.c38002a__arr_name = type { [0 x i32]*, %struct.c38002a__arr___XUB* }
+       %struct.c38002a__rec = type { i32, %struct.c38002a__arr_name }
+
+define void @_ada_c38002a() {
+entry:
+       %0 = invoke i8* @__gnat_malloc(i32 12)
+                       to label %invcont unwind label %lpad            ; <i8*> [#uses=0]
+
+invcont:               ; preds = %entry
+       %1 = invoke i8* @__gnat_malloc(i32 20)
+                       to label %invcont1 unwind label %lpad           ; <i8*> [#uses=0]
+
+invcont1:              ; preds = %invcont
+       %2 = invoke i32 @report__ident_int(i32 2)
+                       to label %.noexc unwind label %lpad             ; <i32> [#uses=0]
+
+.noexc:                ; preds = %invcont1
+       %3 = invoke i32 @report__ident_int(i32 3)
+                       to label %.noexc88 unwind label %lpad           ; <i32> [#uses=0]
+
+.noexc88:              ; preds = %.noexc
+       unreachable
+
+lpad:          ; preds = %.noexc, %invcont1, %invcont, %entry
+       %r.0 = phi %struct.c38002a__rec* [ null, %entry ], [ null, %invcont ], [ null, %invcont1 ], [ null, %.noexc ]           ; <%struct.c38002a__rec*> [#uses=1]
+       %4 = getelementptr %struct.c38002a__rec* %r.0, i32 0, i32 0             ; <i32*> [#uses=1]
+       %5 = load i32* %4, align 4              ; <i32> [#uses=0]
+       ret void
+}
+
+declare i32 @report__ident_int(i32)
+
+declare i8* @__gnat_malloc(i32)

diff --git a/test/CodeGen/X86/split-eh-lpad-edges.ll b/test/CodeGen/X86/split-eh-lpad-edges.ll
index 2cc8e54672b0a3cde8b3159b11346bfe00cc99de..7808ad63168d4864d046515a8437e75574c4dc19 100644 (file)
--- a/test/CodeGen/X86/split-eh-lpad-edges.ll
+++ b/test/CodeGen/X86/split-eh-lpad-edges.ll
@@ -1,4 +1,38 @@
 ; 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*, ...)
+; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin | not grep jmp
 ; rdar://6647639
 ; XFAIL: *