database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-07-30 19:03:16 +03:00
Code Activity

When running wasm-opt, ignore any failure because it will fail for unknown flags and the set of legal flags will change from version to version. Document the size-reduction effect (or non-effect) of a dozen-odd wasm-opt flags and retain those which demonstrate a wasm file size reduction in -Oz builds (our production build mode). Total size savings: roughly 13kb.

Browse Source 
FossilOrigin-Name: c9dc581e0287e3462ac55f80ca76e7e98d31157022052c892517363c45287a7b
This commit is contained in:
stephan
2025-01-23 19:44:09 +00:00
parent 726a047a47
commit 02e81f72a0
3 changed files with 75 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

85
ext/wasm/mkwasmbuilds.c
View File

@ -65,23 +65,74 @@ static void mk_prologue(void){
ps("# --[extern-][pre/post]-js files.");
ps("pre-post-jses.deps.common := $(extern-pre-js.js) $(sqlite3-license-version.js)");
/* SQLITE.CALL.WASM-OPT = shell code to run $(1) (source wasm file
** name) through $(bin.wasm-opt) */
ps("ifeq (,$(bin.wasm-opt))");
ps("define SQLITE.CALL.WASM-OPT");
ps("echo 'wasm-opt not available for $(1)'");
ps("endef");
ps("else");
ps("define SQLITE.CALL.WASM-OPT");
ps("echo -n 'Before wasm-opt:'; ls -l $(1);\\\n"
"\trm -f wasm-opt-tmp.wasm;\\\n"
"\t$(bin.wasm-opt) --enable-bulk-memory-opt --all-features --post-emscripten\\\n"
"\t$(1) -o wasm-opt-tmp.wasm || exit;\\\n"
"\tmv wasm-opt-tmp.wasm $(1); "
"echo -n 'After wasm-opt: '; ls -l $(1)"
);
ps("endef");
ps("endif");
{
/* SQLITE.CALL.WASM-OPT = shell code to run $(1) (source wasm file
** name) through $(bin.wasm-opt) */
const char * zOptFlags =
/*
** Flags for wasm-opt. It has many, many, MANY "passes" options
** and the ones which appear here were selected solely on the
** basis of trial and error.
**
** All wasm file size savings/costs mentioned below are based on
** the vanilla build of sqlite3.wasm with -Oz (our shipping
** configuration). Comments like "saves nothing" may not be
** technically correct: "nothing" means "some neglible amount."
**
** Note that performance gains/losses are _not_ taken into
** account here: only wasm file size.
*/
"--enable-bulk-memory-opt " /* required */
"--all-features " /* required */
"--post-emscripten " /* Saves roughly 12kb */
"--strip-debug " /* We already wasm-strip, but in
** case this environment has no
** wasm-strip... */
/*
** The rest are trial-and-error. See wasm-opt --help and search
** for "Optimization passes" to find the full list.
**
** With many flags this gets unusuably slow.
*/
/*"--converge " saves nothing for the options we're using */
/*"--dce " saves nothing */
/*"--directize " saves nothing */
/*"--gsi " no: requires --closed-world flag, which does not
** sound like something we want. */
/*"--gufa --gufa-cast-all --gufa-optimizing " costs roughly 2kb */
/*"--heap-store-optimization " saves nothing */
/*"--heap2local " saves nothing */
//"--inlining --inlining-optimizing " costs roughly 3kb */
"--local-cse " /* saves roughly 1kb */
/*"--once-reduction " saves nothing */
/*"--remove-memory-init " presumably a performance tweak */
/*"--remove-unused-names " saves nothing */
/*"--safe-heap "*/
/*"--vacuum " saves nothing */
;
ps("ifeq (,$(bin.wasm-opt))");
ps("define SQLITE.CALL.WASM-OPT");
ps("echo 'wasm-opt not available for $(1)'");
ps("endef");
ps("else");
ps("define SQLITE.CALL.WASM-OPT");
pf("echo -n 'Before wasm-opt:'; ls -l $(1);\\\n"
"\trm -f wasm-opt-tmp.wasm;\\\n"
/* It's very likely that the set of wasm-opt flags varies from
** version to version, so we'll ignore any errors here. */
"\tif $(bin.wasm-opt) $(1) -o wasm-opt-tmp.wasm \\\n"
"\t\t%s; then \\\n"
"\t\tmv wasm-opt-tmp.wasm $(1); \\\n"
"\t\techo -n 'After wasm-opt: '; \\\n"
"\t\tls -l $(1); \\\n"
"\telse \\\n"
"\t\techo 'WARNING: ignoring wasm-opt failure'; \\\n"
"\tfi\n",
zOptFlags
);
ps("endef");
ps("endif");
}
}
/*