Determine HLoadClass/String load kind early.

This helps save memory by avoiding the allocation of
HEnvironment and related objects for AOT references to
boot image strings and classes (kBootImage* load kinds)
and also for JIT references (kJitTableAddress).

Compiling aosp_taimen-userdebug boot image, the most memory
hungry method BatteryStats.dumpLocked() needs
  - before:
    Used 55105384 bytes of arena memory...
    ...
    UseListNode    10009704
    Environment      423248
    EnvVRegs       20676560
    ...
  - after:
    Used 50559176 bytes of arena memory...
    ...
    UseListNode     8568936
    Environment      365680
    EnvVRegs       17628704
    ...

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing --jit
Bug: 34053922
Change-Id: I68e73a438e6ac8e8908e6fccf53bbeea8a64a077

1 files changed, 6 insertions, 5 deletions

diff --git a/compiler/optimizing/instruction_builder.h b/compiler/optimizing/instruction_builder.h
index 2446ddb86a..0500d40cd3 100644
--- a/compiler/optimizing/instruction_builder.h
+++ b/compiler/optimizing/instruction_builder.h
@@ -240,9 +240,10 @@ class HInstructionBuilder : public ValueObject {
   // Builds an instruction sequence for a switch statement.
   void BuildSwitch(const Instruction& instruction, uint32_t dex_pc);
 
-  // Builds a `HLoadClass` loading the given `type_index`. If `outer` is true,
-  // this method will use the outer class's dex file to lookup the type at
-  // `type_index`.
+  // Builds a `HLoadString` loading the given `string_index`.
+  void BuildLoadString(dex::StringIndex string_index, uint32_t dex_pc);
+
+  // Builds a `HLoadClass` loading the given `type_index`.
   HLoadClass* BuildLoadClass(dex::TypeIndex type_index, uint32_t dex_pc);
 
   HLoadClass* BuildLoadClass(dex::TypeIndex type_index,
@@ -253,10 +254,10 @@ class HInstructionBuilder : public ValueObject {
       REQUIRES_SHARED(Locks::mutator_lock_);
 
   // Returns the outer-most compiling method's class.
-  mirror::Class* GetOutermostCompilingClass() const;
+  ObjPtr<mirror::Class> GetOutermostCompilingClass() const;
 
   // Returns the class whose method is being compiled.
-  mirror::Class* GetCompilingClass() const;
+  ObjPtr<mirror::Class> GetCompilingClass() const;
 
   // Returns whether `type_index` points to the outer-most compiling method's class.
   bool IsOutermostCompilingClass(dex::TypeIndex type_index) const;