Generate a custom OSR entrypoint for OSR compiles on all platforms, and transition to optimized cod…

src/ia32/lithium-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 14 matching lines @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "lithium-allocator-inl.h"
 #include "ia32/lithium-ia32.h"
 #include "ia32/lithium-codegen-ia32.h"
+#include "hydrogen-osr.h"
 
 namespace v8 {
 namespace internal {
 
 #define DEFINE_COMPILE(type)                            \
   void L##type::CompileToNative(LCodeGen* generator) {  \
     generator->Do##type(this);                          \
   }
 LITHIUM_CONCRETE_INSTRUCTION_LIST(DEFINE_COMPILE)
 #undef DEFINE_COMPILE
@@ skipping 441 matching lines @@
   LPhase phase("L_Building chunk", chunk_);
   status_ = BUILDING;
 
   // Reserve the first spill slot for the state of dynamic alignment.
   if (info()->IsOptimizing()) {
     int alignment_state_index = chunk_->GetNextSpillIndex(false);
     ASSERT_EQ(alignment_state_index, 0);
     USE(alignment_state_index);
   }
 
+  // If compiling for OSR, reserve space for the unoptimized frame,
+  // which will be subsumed into this frame.
+  if (graph()->has_osr()) {
+    for (int i = graph()->osr()->UnoptimizedFrameSlots(); i > 0; i--) {
+      chunk_->GetNextSpillIndex(false);
+    }
+  }
+
   const ZoneList<HBasicBlock*>* blocks = graph()->blocks();
   for (int i = 0; i < blocks->length(); i++) {
     HBasicBlock* next = NULL;
     if (i < blocks->length() - 1) next = blocks->at(i + 1);
     DoBasicBlock(blocks->at(i), next);
     if (is_aborted()) return NULL;
   }
   status_ = DONE;
   return chunk_;
 }
@@ skipping 2084 matching lines @@
     CodeStubInterfaceDescriptor* descriptor =
         info()->code_stub()->GetInterfaceDescriptor(info()->isolate());
     int index = static_cast<int>(instr->index());
     Register reg = DESCRIPTOR_GET_PARAMETER_REGISTER(descriptor, index);
     return DefineFixed(result, reg);
   }
 }
 
 
 LInstruction* LChunkBuilder::DoUnknownOSRValue(HUnknownOSRValue* instr) {
-  int spill_index = chunk()->GetNextSpillIndex(false);  // Not double-width.
-  if (spill_index > LUnallocated::kMaxFixedSlotIndex) {
-    Abort("Too many spill slots needed for OSR");
-    spill_index = 0;
+  // Use an index that corresponds to the location in the unoptimized frame,
+  // which the optimized frame will subsume.
+  int env_index = instr->index();
+  int spill_index = 0;
+  if (instr->environment()->is_parameter_index(env_index)) {
+    spill_index = chunk()->GetParameterStackSlot(env_index);
+  } else {
+    spill_index = env_index - instr->environment()->first_local_index();
+    if (spill_index > LUnallocated::kMaxFixedSlotIndex) {
+      Abort("Too many spill slots needed for OSR");
+      spill_index = 0;
+    }
+    if (spill_index == 0) {
+      // The dynamic frame alignment state overwrites the first local.
+      // The first local is saved at the end of the unoptimized frame.
+      spill_index = graph()->osr()->UnoptimizedFrameSlots();
+    }
   }
   return DefineAsSpilled(new(zone()) LUnknownOSRValue, spill_index);
 }
 
 
 LInstruction* LChunkBuilder::DoCallStub(HCallStub* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   argument_count_ -= instr->argument_count();
   LCallStub* result = new(zone()) LCallStub(context);
   return MarkAsCall(DefineFixed(result, eax), instr);
@@ skipping 163 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32