commit 5f7b58ea1adfc0639dd605b65f59198d3763f801
author Vladimir Marko <vmarko@google.com> Mon Nov 23 19:49:34 2015 +0000
committer Vladimir Marko <vmarko@google.com> Wed Dec 23 09:59:07 2015 +0000
tree 04556e673cdd3967cc967ff79931eab49e523956
parent 1201804d1813d7db0accead9721d67c40b3de564

Rewrite HInstruction::Is/As<type>().

Make Is<type>() and As<type>() non-virtual for concrete
instruction types, relying on GetKind(), and mark GetKind()
as PURE to improve optimization opportunities. This reduces
the number of relocations in libart-compiler.so's .rel.dyn
section by ~4K, or ~44%, and in .data.rel.ro by ~18K, or
~65%. The file is 96KiB smaller for Nexus 5, including 8KiB
reduction of the .text section.

Unfortunately, the g++/clang++ __attribute__((pure)) is not
strong enough to avoid duplicated virtual calls and we would
need the C++ [[pure]] attribute proposed in n3744 instead.
To work around this deficiency, we introduce an extra
non-virtual indirection for GetKind(), so that the compiler
can optimize common expressions such as
    instruction->IsAdd() || instruction->IsSub()
or
    instruction->IsAdd() && instruction->AsAdd()->...
which contain two virtual calls to GetKind() after inlining.

Change-Id: I83787de0671a5cb9f5b0a5f4a536cef239d5b401

compiler/optimizing/code_generator_mips.cc

diff --git a/compiler/optimizing/code_generator_mips.cc b/compiler/optimizing/code_generator_mips.cc
index ae0f2c8..ef6b403 100644
--- a/compiler/optimizing/code_generator_mips.cc
+++ b/compiler/optimizing/code_generator_mips.cc
@@ -2092,7 +2092,7 @@
   }
 }
 
-void LocationsBuilderMIPS::VisitCondition(HCondition* instruction) {
+void LocationsBuilderMIPS::HandleCondition(HCondition* instruction) {
   LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(instruction);
   switch (instruction->InputAt(0)->GetType()) {
     default:
@@ -2112,7 +2112,7 @@
   }
 }
 
-void InstructionCodeGeneratorMIPS::VisitCondition(HCondition* instruction) {
+void InstructionCodeGeneratorMIPS::HandleCondition(HCondition* instruction) {
   if (!instruction->NeedsMaterialization()) {
     return;
   }
@@ -4792,83 +4792,83 @@
 }
 
 void LocationsBuilderMIPS::VisitEqual(HEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitEqual(HEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitNotEqual(HNotEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitNotEqual(HNotEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitLessThan(HLessThan* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitLessThan(HLessThan* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitLessThanOrEqual(HLessThanOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitLessThanOrEqual(HLessThanOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitGreaterThan(HGreaterThan* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitGreaterThan(HGreaterThan* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitGreaterThanOrEqual(HGreaterThanOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitGreaterThanOrEqual(HGreaterThanOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitBelow(HBelow* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitBelow(HBelow* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitBelowOrEqual(HBelowOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitBelowOrEqual(HBelowOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitAbove(HAbove* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitAbove(HAbove* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitAboveOrEqual(HAboveOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void InstructionCodeGeneratorMIPS::VisitAboveOrEqual(HAboveOrEqual* comp) {
-  VisitCondition(comp);
+  HandleCondition(comp);
 }
 
 void LocationsBuilderMIPS::VisitFakeString(HFakeString* instruction) {