Add support for calling entry / exit hooks directly from JIT code

The idea of this CL is to avoid maintaining the instrumentation stack
and manipulating the return addresses on the stack to call the entry /
exit hooks. This Cl only addresses this for JITed code. In follow up
CLs, we will extend this to others (native, nterp). Once we have
everything in place we could remove the complexity of instrumentation
stack.

This CL introduces new nodes (HMethodEntry / HMethodExit(Void)) that
generate code to call the trace entry / exit hooks when
instrumentation_stubs are installed. Currently these are introduced for
JITed code in debuggable mode. The entry / exit hooks roughly do the
same this as instrumentation entry / exit points.
We also extend the JITed frame slots by adding a ShouldDeoptimize slot.
This will be used to force deoptimization of frames when requested by
jvmti (for ex: structural re-definition).

Test: art/testrunner.py
Change-Id: Id4aa439731d214a8d2b820a67e75415ca1d5424e

1 files changed, 11 insertions, 0 deletions

diff --git a/compiler/optimizing/instruction_builder.cc b/compiler/optimizing/instruction_builder.cc
index 390a2bb0be..ed760f190d 100644
--- a/compiler/optimizing/instruction_builder.cc
+++ b/compiler/optimizing/instruction_builder.cc
@@ -372,6 +372,9 @@ bool HInstructionBuilder::Build() {
     if (current_block_->IsEntryBlock()) {
       InitializeParameters();
       AppendInstruction(new (allocator_) HSuspendCheck(0u));
+      if (graph_->IsDebuggable() && code_generator_->GetCompilerOptions().IsJitCompiler()) {
+        AppendInstruction(new (allocator_) HMethodEntryHook(0u));
+      }
       AppendInstruction(new (allocator_) HGoto(0u));
       continue;
     } else if (current_block_->IsExitBlock()) {
@@ -822,10 +825,18 @@ void HInstructionBuilder::BuildReturn(const Instruction& instruction,
           compilation_stats_,
           MethodCompilationStat::kConstructorFenceGeneratedFinal);
     }
+    if (graph_->IsDebuggable() && code_generator_->GetCompilerOptions().IsJitCompiler()) {
+      // Return value is not used for void functions. We pass NullConstant to
+      // avoid special cases when generating code.
+      AppendInstruction(new (allocator_) HMethodExitHook(graph_->GetNullConstant(), dex_pc));
+    }
     AppendInstruction(new (allocator_) HReturnVoid(dex_pc));
   } else {
     DCHECK(!RequiresConstructorBarrier(dex_compilation_unit_));
     HInstruction* value = LoadLocal(instruction.VRegA(), type);
+    if (graph_->IsDebuggable() && code_generator_->GetCompilerOptions().IsJitCompiler()) {
+      AppendInstruction(new (allocator_) HMethodExitHook(value, dex_pc));
+    }
     AppendInstruction(new (allocator_) HReturn(value, dex_pc));
   }
   current_block_ = nullptr;