commit 42249c3602c3d0243396ee3627ffb5906aa77c1e
author Aart Bik <ajcbik@google.com> Thu Jan 07 15:33:50 2016 -0800
committer Aart Bik <ajcbik@google.com> Tue Jan 12 16:39:20 2016 -0800
tree 1e822a21c87331246cbde3923eac88fa315fa2cc
parent 922698ded1e80cad1ecce4c2172a88c76a216373

Reduce code size by sharing slow paths.

Rationale:
Sharing identical slow path code reduces code size.

Background:
Currently, slow paths with the same dex-pc, same physical register
spilling code, and identical stack maps are shared (making this
only useful for deopt slow paths). The newly introduced mechanism
is sufficiently general to allow future improvements by e.g.
allowing different dex-pc (by passing this to runtime) or even
the kind of slow paths (by passing runtime addresses to the slowpath).

Change-Id: I819615c47b4fd98440a241f681f93e4fc22d12e0

compiler/optimizing/code_generator_x86_64.cc

diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index ec62d84..294b40e 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -387,18 +387,16 @@
 
 class DeoptimizationSlowPathX86_64 : public SlowPathCode {
  public:
-  explicit DeoptimizationSlowPathX86_64(HInstruction* instruction)
+  explicit DeoptimizationSlowPathX86_64(HDeoptimize* instruction)
       : instruction_(instruction) {}
 
   void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
     CodeGeneratorX86_64* x86_64_codegen = down_cast<CodeGeneratorX86_64*>(codegen);
     __ Bind(GetEntryLabel());
     SaveLiveRegisters(codegen, instruction_->GetLocations());
-    DCHECK(instruction_->IsDeoptimize());
-    HDeoptimize* deoptimize = instruction_->AsDeoptimize();
     x86_64_codegen->InvokeRuntime(QUICK_ENTRY_POINT(pDeoptimize),
-                                  deoptimize,
-                                  deoptimize->GetDexPc(),
+                                  instruction_,
+                                  instruction_->GetDexPc(),
                                   this);
     CheckEntrypointTypes<kQuickDeoptimize, void, void>();
   }
@@ -406,7 +404,7 @@
   const char* GetDescription() const OVERRIDE { return "DeoptimizationSlowPathX86_64"; }
 
  private:
-  HInstruction* const instruction_;
+  HDeoptimize* const instruction_;
   DISALLOW_COPY_AND_ASSIGN(DeoptimizationSlowPathX86_64);
 };
 
@@ -1000,7 +998,7 @@
 
 InstructionCodeGeneratorX86_64::InstructionCodeGeneratorX86_64(HGraph* graph,
                                                                CodeGeneratorX86_64* codegen)
-      : HGraphVisitor(graph),
+      : InstructionCodeGenerator(graph, codegen),
         assembler_(codegen->GetAssembler()),
         codegen_(codegen) {}
 
@@ -1594,9 +1592,7 @@
 }
 
 void InstructionCodeGeneratorX86_64::VisitDeoptimize(HDeoptimize* deoptimize) {
-  SlowPathCode* slow_path = new (GetGraph()->GetArena())
-      DeoptimizationSlowPathX86_64(deoptimize);
-  codegen_->AddSlowPath(slow_path);
+  SlowPathCode* slow_path = deopt_slow_paths_.NewSlowPath<DeoptimizationSlowPathX86_64>(deoptimize);
   GenerateTestAndBranch(deoptimize,
                         /* condition_input_index */ 0,
                         slow_path->GetEntryLabel(),