Compile skwasm at -Oz. (#42002)

eyebrowsoffire · web-flow · commit 86e5f77e9dbd · 2023-05-15T19:59:14.000Z
We want to start from a place of small size, and optimize from there with skwasm. Since there is no baseline expectation of performance at `-O3`, let's start with the smallest possible binary.
diff --git a/DEPS b/DEPS
@@ -255,7 +255,7 @@ allowed_hosts = [
 ]
 
 deps = {
-  'src': 'https://github.com/flutter/buildroot.git' + '@' + '05ec9f7124191c7ba354521f3ffd34b09af872e7',
+  'src': 'https://github.com/flutter/buildroot.git' + '@' + 'b1e6e81b568b633f05cb9ac4afb465013b774a80',
 
    # Fuchsia compatibility
    #
diff --git a/lib/web_ui/skwasm/BUILD.gn b/lib/web_ui/skwasm/BUILD.gn
@@ -49,11 +49,6 @@ wasm_lib("skwasm") {
       "-sASSERTIONS=1",
       "-sGL_ASSERTIONS=1",
     ]
-  } else {
-    ldflags += [
-      "-Oz",
-      "--closure=1",
-    ]
   }
 
   deps = [
diff --git a/third_party/canvaskit/BUILD.gn b/third_party/canvaskit/BUILD.gn
@@ -85,6 +85,7 @@ wasm_toolchain("skwasm") {
 
     # skwasm is multithreaded
     wasm_use_pthreads = true
+    wasm_prioritize_size = true
   }
 }
 

Original file line number	Diff line number	Diff line change
`@@ -255,7 +255,7 @@ allowed_hosts = [`
`255`	`255`	`]`
`256`	`256`
`257`	`257`	`deps = {`
`258`		`- 'src': 'https://github.com/flutter/buildroot.git' + '@' + '05ec9f7124191c7ba354521f3ffd34b09af872e7',`
	`258`	`+ 'src': 'https://github.com/flutter/buildroot.git' + '@' + 'b1e6e81b568b633f05cb9ac4afb465013b774a80',`
`259`	`259`
`260`	`260`	`# Fuchsia compatibility`
`261`	`261`	`#`
Original file line number	Diff line number	Diff line change
`@@ -49,11 +49,6 @@ wasm_lib("skwasm") {`
`49`	`49`	`"-sASSERTIONS=1",`
`50`	`50`	`"-sGL_ASSERTIONS=1",`
`51`	`51`	`]`
`52`		`- } else {`
`53`		`- ldflags += [`
`54`		`- "-Oz",`
`55`		`- "--closure=1",`
`56`		`- ]`
`57`	`52`	`}`
`58`	`53`
`59`	`54`	`deps = [`
Original file line number	Diff line number	Diff line change
`@@ -85,6 +85,7 @@ wasm_toolchain("skwasm") {`
`85`	`85`
`86`	`86`	`# skwasm is multithreaded`
`87`	`87`	`wasm_use_pthreads = true`
	`88`	`+ wasm_prioritize_size = true`
`88`	`89`	`}`
`89`	`90`	`}`
`90`	`91`