From 14e1438ec0a09c903081bbb6f92437185f634154 Mon Sep 17 00:00:00 2001
From: Ben Vanik <ben.vanik@gmail.com>
Date: Wed, 10 Jun 2015 00:28:02 -0700
Subject: [PATCH] Dramatically speeding up HIR comments.

---
 src/xenia/cpu/frontend/ppc_hir_builder.cc |  9 +++--
 src/xenia/cpu/hir/hir_builder.cc          | 45 +++++++++++++++++------
 src/xenia/cpu/hir/hir_builder.h           |  4 +-
 3 files changed, 42 insertions(+), 16 deletions(-)

diff --git a/src/xenia/cpu/frontend/ppc_hir_builder.cc b/src/xenia/cpu/frontend/ppc_hir_builder.cc
index 8d06ab28e..326d62cac 100644
--- a/src/xenia/cpu/frontend/ppc_hir_builder.cc
+++ b/src/xenia/cpu/frontend/ppc_hir_builder.cc
@@ -56,9 +56,9 @@ bool PPCHIRBuilder::Emit(FunctionInfo* symbol_info, uint32_t flags) {
 
   with_debug_info_ = (flags & EMIT_DEBUG_COMMENTS) == EMIT_DEBUG_COMMENTS;
   if (with_debug_info_) {
-    Comment("%s fn %.8X-%.8X %s", symbol_info->module()->name().c_str(),
-            symbol_info->address(), symbol_info->end_address(),
-            symbol_info->name().c_str());
+    CommentFormat("%s fn %.8X-%.8X %s", symbol_info->module()->name().c_str(),
+                  symbol_info->address(), symbol_info->end_address(),
+                  symbol_info->name().c_str());
   }
 
   // Allocate offset list.
@@ -101,8 +101,9 @@ bool PPCHIRBuilder::Emit(FunctionInfo* symbol_info, uint32_t flags) {
         AnnotateLabel(address, label);
       }
       comment_buffer_.Reset();
+      comment_buffer_.AppendFormat("%.8X %.8X ", address, i.code);
       DisasmPPC(i, &comment_buffer_);
-      Comment("%.8X %.8X %s", address, i.code, comment_buffer_.GetString());
+      Comment(comment_buffer_);
       first_instr = last_instr();
     }
 
diff --git a/src/xenia/cpu/hir/hir_builder.cc b/src/xenia/cpu/hir/hir_builder.cc
index c5eeccfc5..d77e1f634 100644
--- a/src/xenia/cpu/hir/hir_builder.cc
+++ b/src/xenia/cpu/hir/hir_builder.cc
@@ -16,6 +16,9 @@
 #include "xenia/cpu/symbol_info.h"
 #include "xenia/profiling.h"
 
+// Will scribble arena memory to hopefully find use before clears.
+//#define SCRIBBLE_ARENA_ON_RESET
+
 namespace xe {
 namespace cpu {
 namespace hir {
@@ -57,7 +60,7 @@ void HIRBuilder::Reset() {
   locals_.clear();
   block_head_ = block_tail_ = NULL;
   current_block_ = NULL;
-#if XE_DEBUG
+#if SCRIBBLE_ARENA_ON_RESET
   arena_->DebugFill();
 #endif
   arena_->Reset();
@@ -727,18 +730,38 @@ Value* HIRBuilder::CloneValue(Value* source) {
   return value;
 }
 
-void HIRBuilder::Comment(const char* format, ...) {
-  char buffer[1024];
-  va_list args;
-  va_start(args, format);
-  vsnprintf(buffer, 1024, format, args);
-  va_end(args);
-  size_t len = strlen(buffer);
-  if (!len) {
+void HIRBuilder::Comment(const char* value) {
+  size_t length = std::strlen(value);
+  if (!length) {
     return;
   }
-  void* p = arena_->Alloc(len + 1);
-  memcpy(p, buffer, len + 1);
+  void* p = arena_->Alloc(length + 1);
+  std::memcpy(p, value, length + 1);
+  Instr* i = AppendInstr(OPCODE_COMMENT_info, 0);
+  i->src1.offset = (uint64_t)p;
+  i->src2.value = i->src3.value = NULL;
+}
+
+void HIRBuilder::Comment(const StringBuffer& value) {
+  if (!value.length()) {
+    return;
+  }
+  void* p = arena_->Alloc(value.length() + 1);
+  std::memcpy(p, value.GetString(), value.length() + 1);
+  Instr* i = AppendInstr(OPCODE_COMMENT_info, 0);
+  i->src1.offset = (uint64_t)p;
+  i->src2.value = i->src3.value = NULL;
+}
+
+void HIRBuilder::CommentFormat(const char* format, ...) {
+  static const uint32_t kMaxCommentSize = 1024;
+  char* p = reinterpret_cast<char*>(arena_->Alloc(kMaxCommentSize));
+  va_list args;
+  va_start(args, format);
+  size_t chars_written = vsnprintf(p, kMaxCommentSize - 1, format, args);
+  va_end(args);
+  size_t rewind = kMaxCommentSize - chars_written;
+  arena_->Rewind(rewind);
   Instr* i = AppendInstr(OPCODE_COMMENT_info, 0);
   i->src1.offset = (uint64_t)p;
   i->src2.value = i->src3.value = NULL;
diff --git a/src/xenia/cpu/hir/hir_builder.h b/src/xenia/cpu/hir/hir_builder.h
index 36002ff89..89e8d0396 100644
--- a/src/xenia/cpu/hir/hir_builder.h
+++ b/src/xenia/cpu/hir/hir_builder.h
@@ -68,7 +68,9 @@ class HIRBuilder {
   // static allocations:
   // Value* AllocStatic(size_t length);
 
-  void Comment(const char* format, ...);
+  void Comment(const char* value);
+  void Comment(const StringBuffer& value);
+  void CommentFormat(const char* format, ...);
 
   void Nop();