perf(core) Reduce script name and script code copies (#18298)

Reduce the number of copies and allocations of script code by carrying
around ownership/reference information from creation time.

As an advantage, this allows us to maintain the identity of `&'static
str`-based scripts and use v8's external 1-byte strings (to avoid
incorrectly passing non-ASCII strings, debug `assert!`s gate all string
reference paths).

Benchmark results:

Perf improvements -- ~0.1 - 0.2ms faster, but should reduce garbage
w/external strings and reduces data copies overall. May also unlock some
more interesting optimizations in the future.

This requires adding some generics to functions, but manual
monomorphization has been applied (outer/inner function) to avoid code
bloat.

1 files changed, 4 insertions, 3 deletions

diff --git a/runtime/build.rs b/runtime/build.rs
index 016ece810..ec7c9642c 100644
--- a/runtime/build.rs
+++ b/runtime/build.rs
@@ -17,11 +17,12 @@ mod startup_snapshot {
   use deno_core::snapshot_util::*;
   use deno_core::Extension;
   use deno_core::ExtensionFileSource;
+  use deno_core::ModuleCode;
   use std::path::Path;
 
   fn transpile_ts_for_snapshotting(
     file_source: &ExtensionFileSource,
-  ) -> Result<String, AnyError> {
+  ) -> Result<ModuleCode, AnyError> {
     let media_type = MediaType::from_path(Path::new(&file_source.specifier));
 
     let should_transpile = match media_type {
@@ -41,7 +42,7 @@ mod startup_snapshot {
 
     let parsed = deno_ast::parse_module(ParseParams {
       specifier: file_source.specifier.to_string(),
-      text_info: SourceTextInfo::from_string(code),
+      text_info: SourceTextInfo::from_string(code.take_as_string()),
       media_type,
       capture_tokens: false,
       scope_analysis: false,
@@ -53,7 +54,7 @@ mod startup_snapshot {
       ..Default::default()
     })?;
 
-    Ok(transpiled_source.text)
+    Ok(transpiled_source.text.into())
   }
 
   #[derive(Clone)]