polkawasm: implement actual GC that frees memory via extfree

builder/build.go

@@ -816,21 +816,33 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 					args = append(args, "--asyncify")
 				}
 
-				args = append(args,
-					opt,
-					"-g",
-					result.Executable,
-					"--output", result.Executable,
-				)
-
 				if config.Target.Triple == "wasm32-unknown-polkawasm" {
-					args = append(args, "--signext-lowering")
+					args = append(args,
+						opt,
+						"--signext-lowering",
+						// "--signature-pruning",
+						// "--const-hoisting",
+						// "--mvp-features",
+						result.Executable,
+						"--output",
+						result.Executable,
+					)
+				} else {
+					args = append(args,
+						opt,
+						"-g",
+						result.Executable,
+						"--output",
+						result.Executable,
+					)
 				}
 
 				cmd := exec.Command(goenv.Get("WASMOPT"), args...)
 				cmd.Stdout = os.Stdout
 				cmd.Stderr = os.Stderr
 
+				println(cmd.String())
+
 				err := cmd.Run()
 				if err != nil {
 					return fmt.Errorf("wasm-opt failed: %w", err)

compileopts/config.go

@@ -152,6 +152,8 @@ func (c *Config) OptLevel() (level string, speedLevel, sizeLevel int) {
 		return "O1", 1, 0
 	case "2":
 		return "O2", 2, 0
+	case "3":
+		return "O3", 2, 0
 	case "s":
 		return "Os", 2, 1
 	case "z":

compileopts/options.go

@@ -13,7 +13,7 @@ var (
 	validSerialOptions        = []string{"none", "uart", "usb"}
 	validPrintSizeOptions     = []string{"none", "short", "full"}
 	validPanicStrategyOptions = []string{"print", "trap"}
-	validOptOptions           = []string{"none", "0", "1", "2", "s", "z"}
+	validOptOptions           = []string{"none", "0", "1", "2", "3", "s", "z"}
 )
 
 // Options contains extra options to give to the compiler. These options are

main.go

@@ -1406,7 +1406,7 @@ func main() {
 	}
 	command := os.Args[1]
 
-	opt := flag.String("opt", "z", "optimization level: 0, 1, 2, s, z")
+	opt := flag.String("opt", "z", "optimization level: 0, 1, 2, 3, s, z")
 	gc := flag.String("gc", "", "garbage collector to use (none, leaking, conservative)")
 	panicStrategy := flag.String("panic", "print", "panic strategy (print, trap)")
 	scheduler := flag.String("scheduler", "", "which scheduler to use (none, tasks, asyncify)")

src/runtime/gc_custom.go

@@ -1,4 +1,4 @@
-//go:build gc.custom
+//go:build gc.custom_wip
 
 package runtime
 
@@ -61,31 +61,21 @@ func setHeapEnd(newHeapEnd uintptr) {
 //
 //go:noinline
 func alloc(size uintptr, layout unsafe.Pointer) unsafe.Pointer {
-	printstr("call alloc(")
-	printnum(int(size))
-	printstr(")\n")
-
 	if size == 0 {
 		return unsafe.Pointer(&zeroSizedAlloc)
 	}
 
-	printstr("\ttotal memory ")
-	printnum(int(gcTotalAlloc))
-	printstr("\n")
-
-	size = align(size)
+	size += align(unsafe.Sizeof(layout))
 
 	// Try to bound heap growth.
 	if gcTotalAlloc+uint64(size) < gcTotalAlloc {
-		printstr("\tout of memory\n")
 		abort()
 	}
 
 	// Allocate the memory.
 	pointer := extalloc(size)
 	if pointer == nil {
-		printstr("\textalloc call failed\n")
-		abort()
+		gcAllocPanic()
 	}
 
 	// Zero-out the allocated memory
@@ -105,19 +95,13 @@ func free(ptr unsafe.Pointer) {
 
 // markRoots is called with the start and end addresses to scan for references.
 // It is currently only called with the top and bottom of the stack.
-func markRoots(start, end uintptr) {
-
-}
+func markRoots(start, end uintptr) {}
 
 // GC is called to explicitly run garbage collection.
-func GC() {
-
-}
+func GC() {}
 
 // SetFinalizer registers a finalizer.
-func SetFinalizer(obj interface{}, finalizer interface{}) {
-
-}
+func SetFinalizer(obj interface{}, finalizer interface{}) {}
 
 // ReadMemStats populates m with memory statistics.
 func ReadMemStats(ms *MemStats) {