Make CTX allocatable by the register allocator.

runtime/vm/flow_graph_compiler.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_XXX.
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
@@ skipping 207 matching lines @@
       FLAG_deoptimize_filter != NULL &&
       strstr(parsed_function().function().ToFullyQualifiedCString(),
              FLAG_deoptimize_filter) != NULL) {
     return true;
   }
   return false;
 }
 
 
 static bool IsEmptyBlock(BlockEntryInstr* block) {
-  return !block->HasNonRedundantParallelMove() &&
+  return !block->IsCatchBlockEntry() &&
+         !block->HasNonRedundantParallelMove() &&
          block->next()->IsGoto() &&
          !block->next()->AsGoto()->HasNonRedundantParallelMove();
 }
 
 
 void FlowGraphCompiler::CompactBlock(BlockEntryInstr* block) {
   BlockInfo* block_info = block_info_[block->postorder_number()];
 
   // Break out of cycles in the control flow graph.
   if (block_info->is_marked()) {
@@ skipping 41 matching lines @@
 
 
 void FlowGraphCompiler::EmitInstructionPrologue(Instruction* instr) {
   if (!is_optimizing()) {
     if (instr->CanBecomeDeoptimizationTarget() && !instr->IsGoto()) {
       // Instructions that can be deoptimization targets need to record kDeopt
       // PcDescriptor corresponding to their deopt id. GotoInstr records its
       // own so that it can control the placement.
       AddCurrentDescriptor(RawPcDescriptors::kDeopt,
                            instr->deopt_id(),
-                           Scanner::kNoSourcePos);
+                           instr->token_pos());
     }
     AllocateRegistersLocally(instr);
   } else if (instr->MayThrow()  &&
              (CurrentTryIndex() != CatchClauseNode::kInvalidTryIndex)) {
     // Optimized try-block: Sync locals to fixed stack locations.
     EmitTrySync(instr, CurrentTryIndex());
   }
 }
 
 
@@ skipping 800 matching lines @@
     }
   }
 
   if (locs->out(0).IsRegister()) {
     // Fixed output registers are allowed to overlap with
     // temps and inputs.
     blocked_registers[locs->out(0).reg()] = true;
   }
 
   // Do not allocate known registers.
-  blocked_registers[CTX] = true;
   blocked_registers[SPREG] = true;
   blocked_registers[FPREG] = true;
   if (TMP != kNoRegister) {
     blocked_registers[TMP] = true;
   }
   if (TMP2 != kNoRegister) {
     blocked_registers[TMP2] = true;
   }
   if (PP != kNoRegister) {
     blocked_registers[PP] = true;
@@ skipping 256 matching lines @@
   return (reg != kNoRegister) ? (1 << reg) : 0;
 }
 
 
 ParallelMoveResolver::ScratchRegisterScope::ScratchRegisterScope(
     ParallelMoveResolver* resolver, Register blocked)
     : resolver_(resolver),
       reg_(kNoRegister),
       spilled_(false) {
   uword blocked_mask = MaskBit(blocked)
-                     | MaskBit(CTX)
                      | MaskBit(SPREG)
                      | MaskBit(FPREG)
                      | MaskBit(TMP)
                      | MaskBit(TMP2)
                      | MaskBit(PP);
   if (resolver->compiler_->intrinsic_mode()) {
     // Block additional registers that must be preserved for intrinsics.
     blocked_mask |= MaskBit(ARGS_DESC_REG);
   }
   reg_ = static_cast<Register>(
@@ skipping 92 matching lines @@
     threshold = FLAG_optimization_counter_scale * basic_blocks +
         FLAG_min_optimization_counter_threshold;
     if (threshold > FLAG_optimization_counter_threshold) {
       threshold = FLAG_optimization_counter_threshold;
     }
   }
   return threshold;
 }
 
 }  // namespace dart