[asm.js] Tune initial buffer sizes and growing strategy.

This simplifies the growing strategy used in {ZoneBuffer} and also tunes the initial sizes used for various instances of these buffers. Note that such a {ZoneBuffer} is used for entire modules and individual function bodies. [email protected] Change-Id: I99a0898589984e1830c681845fabb0ed5f8317ab Reviewed-on: https://chromium-review.googlesource.com/508711 Commit-Queue: Michael Starzinger <[email protected]> Reviewed-by: Clemens Hammacher <[email protected]> Cr-Commit-Position: refs/heads/master@{#45419}
zhuzhuaicoding · May 19, 2017 · ad7caee · ad7caee
1 parent 0980d75
commit ad7caee
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Showing 2 changed files with 3 additions and 3 deletions.
diff --git a/src/wasm/wasm-module-builder.cc b/src/wasm/wasm-module-builder.cc
@@ -47,7 +47,7 @@ WasmFunctionBuilder::WasmFunctionBuilder(WasmModuleBuilder* builder)
       locals_(builder->zone()),
       signature_index_(0),
       func_index_(static_cast<uint32_t>(builder->functions_.size())),
-      body_(builder->zone()),
+      body_(builder->zone(), 256),
       i32_temps_(builder->zone()),
       i64_temps_(builder->zone()),
       f32_temps_(builder->zone()),

diff --git a/src/wasm/wasm-module-builder.h b/src/wasm/wasm-module-builder.h
@@ -20,7 +20,7 @@ namespace wasm {
 
 class ZoneBuffer : public ZoneObject {
  public:
-  static const uint32_t kInitialSize = 4096;
+  static constexpr size_t kInitialSize = 1024;
   explicit ZoneBuffer(Zone* zone, size_t initial = kInitialSize)
       : zone_(zone), buffer_(reinterpret_cast<byte*>(zone->New(initial))) {
     pos_ = buffer_;
@@ -125,7 +125,7 @@ class ZoneBuffer : public ZoneObject {
 
   void EnsureSpace(size_t size) {
     if ((pos_ + size) > end_) {
-      size_t new_size = 4096 + size + (end_ - buffer_) * 3;
+      size_t new_size = size + (end_ - buffer_) * 2;
       byte* new_buffer = reinterpret_cast<byte*>(zone_->New(new_size));
       memcpy(new_buffer, buffer_, (pos_ - buffer_));
       pos_ = new_buffer + (pos_ - buffer_);