Minor optimizations, mainly for Reals in the wasm interpreter

src-js/interpret.js

@@ -235,11 +235,16 @@ intp = new Uint8Array(intp);
 	if (scriptArgs.indexOf('--extract-code') >= 0) {
 		var obj = wasmExtractCode(intp.module, 'best');
 
+		const extractable = ['interpret'];
+
 		var exports = {};
 		for (var f in intp.instance.exports)
 			exports[intp.instance.exports[f].name] = f;
 
-		obj.segments.filter(seg => seg.kind == 0).map(function (seg) {
+		obj.segments.filter(function (seg) {
+			return seg.kind == 0 &&
+				extractable.indexOf(exports[seg.funcIndex]) >= 0;
+		}).map(function (seg) {
 			var name = seg.funcIndex in exports ? exports[seg.funcIndex] : ('_'+seg.funcIndex);
 			var filename = 'disas-'+name+'.bin';
 			var code = obj.code.subarray(seg.funcBodyBegin, seg.funcBodyEnd);

tools/interpretergen-wasm/wasm.icl

@@ -281,7 +281,14 @@ optimize set e = case e of
 	Ediv t signed a b -> Ediv t signed (optimize set a) (optimize set b)
 	Erem t signed a b -> Erem t signed (optimize set a) (optimize set b)
 
-	Eeq t a b -> Eeq t (optimize set a) (optimize set b)
+	Eeq t a b -> case oa of
+		Econst _ v | is_zero v -> Eeqz t ob
+		_ -> case ob of
+			Econst _ v | is_zero v -> Eeqz t oa
+			_ -> Eeq t oa ob
+	with
+		oa = optimize set a
+		ob = optimize set b
 	Ene t a b -> Ene t (optimize set a) (optimize set b)
 	Elt t signed a b -> Elt t signed (optimize set a) (optimize set b)
 	Egt t signed a b -> Egt t signed (optimize set a) (optimize set b)
@@ -306,7 +313,13 @@ optimize set e = case e of
 		e
 			-> Ewrap to fr e
 	Eextend      to fr e -> Eextend      to fr (optimize set e)
-	Ereinterpret to fr e -> Ereinterpret to fr (optimize set e)
+
+	Ereinterpret to fr e -> case optimize set e of
+		Eload ltype stype signed o a | fr==ltype
+			-> Eload to stype signed o a
+		e
+			-> Ereinterpret to fr e
+
 	Etrunc   to fr e -> Etrunc   to fr (optimize set e)
 	Econvert to fr e -> Econvert to fr (optimize set e)