Revert "CFG rework for explicit exception edges"

This reverts commit 8b503db0432981c6b0b2271723f9bcf9448a554a.

Change-Id: I21d5255d827c63de6a229ef419f372fbcf4d16ed

1 files changed, 10 insertions, 111 deletions

diff --git a/src/compiler/codegen/MethodBitcode.cc b/src/compiler/codegen/MethodBitcode.cc
index b2cbc699bb..864372a544 100644
--- a/src/compiler/codegen/MethodBitcode.cc
+++ b/src/compiler/codegen/MethodBitcode.cc
@@ -51,7 +51,7 @@ void defineValue(CompilationUnit* cUnit, llvm::Value* val, int sReg)
   llvm::Value* placeholder = getLLVMValue(cUnit, sReg);
   if (placeholder == NULL) {
     // This can happen on instruction rewrite on verification failure
-    LOG(WARNING) << "Null placeholder";
+    LOG(WARNING) << "Null placeholder - invalid CFG";
     return;
   }
   placeholder->replaceAllUsesWith(val);
@@ -307,6 +307,7 @@ void convertThrow(CompilationUnit* cUnit, RegLocation rlSrc)
   llvm::Function* func = cUnit->intrinsic_helper->GetIntrinsicFunction(
       greenland::IntrinsicHelper::Throw);
   cUnit->irb->CreateCall(func, src);
+  cUnit->irb->CreateUnreachable();
 }
 
 void convertMonitorEnterExit(CompilationUnit* cUnit, int optFlags,
@@ -811,15 +812,6 @@ bool convertMIRNode(CompilationUnit* cUnit, MIR* mir, BasicBlock* bb,
 
   bool objectDefinition = false;
 
-  if (cUnit->printMe) {
-    if ((int)opcode < kMirOpFirst) {
-      LOG(INFO) << ".. " << Instruction::Name(opcode) << " 0x"
-                << std::hex << (int)opcode;
-    } else {
-      LOG(INFO) << ".. opcode 0x" << std::hex << (int)opcode;
-    }
-  }
-
   /* Prep Src and Dest locations */
   int nextSreg = 0;
   int nextLoc = 0;
@@ -1300,24 +1292,10 @@ bool convertMIRNode(CompilationUnit* cUnit, MIR* mir, BasicBlock* bb,
 
    case Instruction::THROW:
       convertThrow(cUnit, rlSrc[0]);
-      /*
-       * If this throw is standalone, terminate.
-       * If it might rethrow, force termination
-       * of the following block.
-       */
-      if (bb->fallThrough == NULL) {
-        cUnit->irb->CreateUnreachable();
-      } else {
-        bb->fallThrough->fallThrough = NULL;
-        bb->fallThrough->taken = NULL;
-      }
       break;
 
    case Instruction::THROW_VERIFICATION_ERROR:
       convertThrowVerificationError(cUnit, vA, vB);
-      UNIMPLEMENTED(WARNING) << "Need dead code elimination pass"
-                             << " - disabling bitcode verification";
-      cUnit->enableDebug &= ~(1 << kDebugVerifyBitcode);
       break;
 
     case Instruction::MOVE_RESULT_WIDE:
@@ -1328,8 +1306,7 @@ bool convertMIRNode(CompilationUnit* cUnit, MIR* mir, BasicBlock* bb,
        * Instruction rewriting on verification failure can eliminate
        * the invoke that feeds this move0result.  It won't ever be reached,
        * so we can ignore it.
-       * TODO: verify that previous instruction is THROW_VERIFICATION_ERROR,
-       * or better, add dead-code elimination.
+       * TODO: verify that previous instruction if THROW_VERIFICATION_ERROR
        */
       UNIMPLEMENTED(WARNING) << "Need to verify previous inst was rewritten";
 #else
@@ -1672,13 +1649,6 @@ void convertExtendedMIR(CompilationUnit* cUnit, BasicBlock* bb, MIR* mir,
       UNIMPLEMENTED(WARNING) << "unimp kMirOpPhi";
       break;
     }
-    case kMirOpNop:
-      if ((mir == bb->lastMIRInsn) && (bb->taken == NULL) &&
-          (bb->fallThrough == NULL)) {
-        cUnit->irb->CreateUnreachable();
-      }
-      break;
-
 #if defined(TARGET_ARM)
     case kMirOpFusedCmplFloat:
       UNIMPLEMENTED(WARNING) << "unimp kMirOpFusedCmpFloat";
@@ -1750,16 +1720,6 @@ bool methodBlockBitcodeConversion(CompilationUnit* cUnit, BasicBlock* bb)
   cUnit->irb->SetInsertPoint(llvmBB);
   setDexOffset(cUnit, bb->startOffset);
 
-  if (cUnit->printMe) {
-    LOG(INFO) << "................................";
-    LOG(INFO) << "Block id " << bb->id;
-    if (llvmBB != NULL) {
-      LOG(INFO) << "label " << llvmBB->getName().str().c_str();
-    } else {
-      LOG(INFO) << "llvmBB is NULL";
-    }
-  }
-
   if (bb->blockType == kEntryBlock) {
     setMethodInfo(cUnit);
     bool *canBeRef = (bool*)  oatNew(cUnit, sizeof(bool) *
@@ -1799,6 +1759,8 @@ bool methodBlockBitcodeConversion(CompilationUnit* cUnit, BasicBlock* bb)
     /*
      * Because we're deferring null checking, delete the associated empty
      * exception block.
+     * TODO: add new block type for exception blocks that we generate
+     * greenland code for.
      */
     llvmBB->eraseFromParent();
     return false;
@@ -1808,9 +1770,8 @@ bool methodBlockBitcodeConversion(CompilationUnit* cUnit, BasicBlock* bb)
 
     setDexOffset(cUnit, mir->offset);
 
-    int opcode = mir->dalvikInsn.opcode;
-    Instruction::Format dalvikFormat =
-        Instruction::FormatOf(mir->dalvikInsn.opcode);
+    Instruction::Code dalvikOpcode = mir->dalvikInsn.opcode;
+    Instruction::Format dalvikFormat = Instruction::FormatOf(dalvikOpcode);
 
     /* If we're compiling for the debugger, generate an update callout */
     if (cUnit->genDebugger) {
@@ -1818,43 +1779,7 @@ bool methodBlockBitcodeConversion(CompilationUnit* cUnit, BasicBlock* bb)
       //genDebuggerUpdate(cUnit, mir->offset);
     }
 
-    if (opcode == kMirOpCheck) {
-      // Combine check and work halves of throwing instruction.
-      MIR* workHalf = mir->meta.throwInsn;
-      mir->dalvikInsn.opcode = workHalf->dalvikInsn.opcode;
-      opcode = mir->dalvikInsn.opcode;
-      SSARepresentation* ssaRep = workHalf->ssaRep;
-      workHalf->ssaRep = mir->ssaRep;
-      mir->ssaRep = ssaRep;
-      workHalf->dalvikInsn.opcode = static_cast<Instruction::Code>(kMirOpNop);
-      if (bb->successorBlockList.blockListType == kCatch) {
-        llvm::Function* intr = cUnit->intrinsic_helper->GetIntrinsicFunction(
-            greenland::IntrinsicHelper::CatchTargets);
-        llvm::Value* switchKey =
-            cUnit->irb->CreateCall(intr, cUnit->irb->getInt32(mir->offset));
-        GrowableListIterator iter;
-        oatGrowableListIteratorInit(&bb->successorBlockList.blocks, &iter);
-        // New basic block to use for work half
-        llvm::BasicBlock* workBB =
-            llvm::BasicBlock::Create(*cUnit->context, "", cUnit->func);
-        llvm::SwitchInst* sw =
-            cUnit->irb->CreateSwitch(switchKey, workBB,
-                                     bb->successorBlockList.blocks.numUsed);
-        while (true) {
-          SuccessorBlockInfo *successorBlockInfo =
-              (SuccessorBlockInfo *) oatGrowableListIteratorNext(&iter);
-          if (successorBlockInfo == NULL) break;
-          llvm::BasicBlock *target =
-              getLLVMBlock(cUnit, successorBlockInfo->block->id);
-          int typeIndex = successorBlockInfo->key;
-          sw->addCase(cUnit->irb->getInt32(typeIndex), target);
-        }
-        llvmBB = workBB;
-        cUnit->irb->SetInsertPoint(llvmBB);
-      }
-    }
-
-    if (opcode >= kMirOpFirst) {
+    if ((int)mir->dalvikInsn.opcode >= (int)kMirOpFirst) {
       convertExtendedMIR(cUnit, bb, mir, llvmBB);
       continue;
     }
@@ -1862,9 +1787,8 @@ bool methodBlockBitcodeConversion(CompilationUnit* cUnit, BasicBlock* bb)
     bool notHandled = convertMIRNode(cUnit, mir, bb, llvmBB,
                                      NULL /* labelList */);
     if (notHandled) {
-      Instruction::Code dalvikOpcode = static_cast<Instruction::Code>(opcode);
       LOG(WARNING) << StringPrintf("%#06x: Op %#x (%s) / Fmt %d not handled",
-                                   mir->offset, opcode,
+                                   mir->offset, dalvikOpcode,
                                    Instruction::Name(dalvikOpcode),
                                    dalvikFormat);
     }
@@ -2062,14 +1986,7 @@ void oatMethodMIR2Bitcode(CompilationUnit* cUnit)
   cUnit->irb->SetInsertPoint(cUnit->entryBB);
   cUnit->irb->CreateBr(cUnit->entryTargetBB);
 
-  if (cUnit->enableDebug & (1 << kDebugVerifyBitcode)) {
-     if (llvm::verifyFunction(*cUnit->func, llvm::PrintMessageAction)) {
-       LOG(INFO) << "Bitcode verification FAILED for "
-                 << PrettyMethod(cUnit->method_idx, *cUnit->dex_file)
-                 << " of size " << cUnit->insnsSize;
-       cUnit->enableDebug |= (1 << kDebugDumpBitcodeFile);
-     }
-  }
+  //llvm::verifyFunction(*cUnit->func, llvm::PrintMessageAction);
 
   if (cUnit->enableDebug & (1 << kDebugDumpBitcodeFile)) {
     // Write bitcode to file
@@ -3214,24 +3131,6 @@ bool methodBitcodeBlockCodeGen(CompilationUnit* cUnit, llvm::BasicBlock* bb)
               cvtShiftOp(cUnit, Instruction::USHR_INT, callInst);
               break;
 
-            case greenland::IntrinsicHelper::CatchTargets: {
-                llvm::SwitchInst* swInst =
-                    llvm::dyn_cast<llvm::SwitchInst>(nextIt);
-                DCHECK(swInst != NULL);
-                /*
-                 * Discard the edges and the following conditional branch.
-                 * Do a direct branch to the default target (which is the
-                 * "work" portion of the pair.
-                 * TODO: awful code layout - rework
-                 */
-                 llvm::BasicBlock* targetBB = swInst->getDefaultDest();
-                 DCHECK(targetBB != NULL);
-                 opUnconditionalBranch(cUnit,
-                                       cUnit->blockToLabelMap.Get(targetBB));
-                 ++it;
-              }
-              break;
-
             default:
               LOG(FATAL) << "Unexpected intrinsic " << (int)id << ", "
                          << cUnit->intrinsic_helper->GetName(id);