tint: Optimize sem node lookup
Add a 'NodeID' to each ast::Node which is the sequentially allocated
index of the node. Use this in sem::Info to map the AST node to the
semantic node, instead of using a std::unordered_map.
Optimised very hot code by entirely eliminating map lookups, and
dramatically reducing cache misses (lookups are usually sequentually
ordered).
Timings running
'webgpu:shader,execution,expression,call,builtin,atan2:f32:inputSource="const";vectorize="_undef_"'
with dawn/node, using SwiftShader:
Without change: 3.22647107s
With change: 3.10578879s
Bug: tint:1613
Change-Id: I22ec48d933b2e5f9da04494bff4e979e6f7b1982
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/96140
Commit-Queue: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
diff --git a/src/tint/ast/block_statement.cc b/src/tint/ast/block_statement.cc
index 7d4f492..4b39121 100644
--- a/src/tint/ast/block_statement.cc
+++ b/src/tint/ast/block_statement.cc
@@ -20,8 +20,11 @@
namespace tint::ast {
-BlockStatement::BlockStatement(ProgramID pid, const Source& src, const StatementList& stmts)
- : Base(pid, src), statements(std::move(stmts)) {
+BlockStatement::BlockStatement(ProgramID pid,
+ NodeID nid,
+ const Source& src,
+ const StatementList& stmts)
+ : Base(pid, nid, src), statements(std::move(stmts)) {
for (auto* stmt : statements) {
TINT_ASSERT(AST, stmt);
TINT_ASSERT_PROGRAM_IDS_EQUAL_IF_VALID(AST, stmt, program_id);
