optimizing separately with wasm-opt (from binaryen 108) (#18)

Author: vbar

c2wasm-api/src/index.ts

@@ -1,6 +1,6 @@
 import fastify from 'fastify';
 import fs from 'fs';
-import { mkdirSync, writeFileSync, existsSync, openSync, closeSync, readFileSync, readdirSync, rmSync, unlinkSync, fstat } from "fs";
+import { mkdirSync, writeFileSync, existsSync, openSync, closeSync, readFileSync, renameSync, readdirSync, rmSync, unlinkSync, fstat } from "fs";
 import { deflateSync } from "zlib";
 import { execSync } from "child_process";
 import { z } from 'zod';
@@ -100,13 +100,9 @@ function shell_exec(cmd: string, cwd: string) {
   return result;
 }
 
-function get_clang_options(options: string) {
-  const clang_flags = `--sysroot=${sysroot} -xc -I/app/clang/includes -fdiagnostics-print-source-range-info -Werror=implicit-function-declaration`;
+function get_optimization_options(options: string) {
   const optimization_options = [
-    '-O0', '-O1', '-O2', '-O3', '-O4', '-Os'
-  ];
-  const miscellaneous_options = [
-    '-ffast-math', '-fno-inline', '-std=c99', '-std=c89'
+    /* default '-O0' not included */ '-O1', '-O2', '-O3', '-O4', '-Os'
   ];
 
   let safe_options = '';
@@ -116,10 +112,16 @@ function get_clang_options(options: string) {
     }
   }
 
-  if (!safe_options) {
-    safe_options += ' -O0';
-  }
+  return safe_options;
+}
 
+function get_clang_options(options: string) {
+  const clang_flags = `--sysroot=${sysroot} -xc -I/app/clang/includes -fdiagnostics-print-source-range-info -Werror=implicit-function-declaration`;
+  const miscellaneous_options = [
+    '-ffast-math', '-fno-inline', '-std=c99', '-std=c89'
+  ];
+
+  let safe_options = '';
   for (let o of miscellaneous_options) {
     if (options.includes(o)) {
       safe_options += ' ' + o;
@@ -182,6 +184,29 @@ function link_c_files(source_files: string[], compile_options: string, link_opti
   return true;
 }
 
+function optimize_wasm(cwd: string, inplace: string, opt_options: string, result_obj: Task) {
+  const unopt = cwd + '/unopt.wasm';
+  const cmd = 'wasm-opt ' + opt_options + ' -o ' + inplace + ' ' + unopt;
+  const out = openSync(cwd + '/opt.log', 'w');
+  let error = '';
+  let success = true;
+  try {
+    renameSync(inplace, unopt);
+    execSync(cmd, { cwd, stdio: [null, out, out], });
+  } catch (ex: unknown) {
+    success = false;
+    if (ex instanceof Error) {
+      error = ex?.message;
+    }
+  } finally {
+    closeSync(out);
+  }
+  const out_msg = readFileSync(cwd + '/opt.log').toString() || error;
+  result_obj.console = sanitize_shell_output(out_msg);
+  result_obj.success = success;
+  return success;
+}
+
 function clean_wasm(cwd: string, inplace: string, result_obj: Task) {
   const cmd = 'hook-cleaner ' + inplace;
   const out = openSync(cwd + '/cleanout.log', 'w');
@@ -199,7 +224,7 @@ function clean_wasm(cwd: string, inplace: string, result_obj: Task) {
   }
   const out_msg = readFileSync(cwd + '/cleanout.log').toString() || error;
   result_obj.console = sanitize_shell_output(out_msg);
-  result_obj.success = false;
+  result_obj.success = success;
   return success;
 }
 
@@ -274,6 +299,17 @@ function build_project(project: RequestBody, base: string) {
     return complete(false, 'Build error');
   }
 
+  const opt_options = get_optimization_options(options || '');
+  if (opt_options) {
+    const opt_obj = {
+      name: 'optimizing wasm'
+    };
+    build_result.tasks.push(opt_obj);
+    if (!optimize_wasm(dir, result, opt_options, opt_obj)) {
+      return complete(false, 'Optimization error');
+    }
+  }
+
   if (strip) {
     const clean_obj = {
       name: 'cleaning wasm'

docker/Dockerfile

@@ -11,6 +11,7 @@ COPY c2wasm-api/tsconfig.json .
 COPY c2wasm-api/src ./src
 COPY wasi-sdk ./clang/wasi-sdk
 COPY hook-cleaner /usr/bin
+COPY wasm-opt /usr/bin
 COPY run.sh .
 ADD compile_flags.txt /etc/clangd/compile_flags.txt
 ADD .clang-tidy /work/.clang-tidy