[turbofan] Collect invocation counts and compute relative call frequencies.

src/full-codegen/arm/full-codegen-arm.cc

Index: src/full-codegen/arm/full-codegen-arm.cc
diff --git a/src/full-codegen/arm/full-codegen-arm.cc b/src/full-codegen/arm/full-codegen-arm.cc
index 3e020a4365591b9ab3e231ed3f829df2b06f1f6b..e1c0bdf1df03fc531a0af736d810e2408a73696e 100644
--- a/src/full-codegen/arm/full-codegen-arm.cc
+++ b/src/full-codegen/arm/full-codegen-arm.cc
@@ -128,6 +128,17 @@ void FullCodeGenerator::Generate() {
   info->set_prologue_offset(masm_->pc_offset());
   __ Prologue(info->GeneratePreagedPrologue());
 
+  // Increment invocation count for the function.
+  __ ldr(r2, FieldMemOperand(r1, JSFunction::kLiteralsOffset));

[Michael Starzinger, 2016/09/14 07:53:45]

suggestion: We could even add a code comment (the ones visible in the
disassembly via --code-comments) for this block.

[mvstanton, 2016/09/14 09:26:09]

Let's certainly do so!

[Benedikt Meurer, 2016/09/14 10:55:44]

Done.

+  __ ldr(r2, FieldMemOperand(r2, LiteralsArray::kFeedbackVectorOffset));
+  __ ldr(r9, FieldMemOperand(
+                 r2, TypeFeedbackVector::kInvocationCountIndex * kPointerSize +
+                         TypeFeedbackVector::kHeaderSize));
+  __ add(r9, r9, Operand(Smi::FromInt(1)));
+  __ str(r9, FieldMemOperand(
+                 r2, TypeFeedbackVector::kInvocationCountIndex * kPointerSize +
+                         TypeFeedbackVector::kHeaderSize));
+
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
     // Generators allocate locals, if any, in context slots.