wasm: remove dependency on thirdparty/binaryen, webassembly backend rewrite (#18120)

vlib/wasm/encoding.v

@@ -110,26 +110,22 @@ fn (mut mod Module) patch(ft Function) {
 	mod.buf << ft.code[ptr..]
 }
 
-// name
-pub fn (mut mod Module) name(name string) {
+fn (mut mod Module) name(name string) {
 	mod.u32(u32(name.len))
 	mod.buf << name.bytes()
 }
 
-// start_subsection
-pub fn (mut mod Module) start_subsection(sec Subsection) int {
+fn (mut mod Module) start_subsection(sec Subsection) int {
 	mod.buf << u8(sec)
 	return mod.patch_start()
 }
 
-// start_section
-pub fn (mut mod Module) start_section(sec Section) int {
+fn (mut mod Module) start_section(sec Section) int {
 	mod.buf << u8(sec)
 	return mod.patch_start()
 }
 
-// end_section
-pub fn (mut mod Module) end_section(tpatch int) {
+fn (mut mod Module) end_section(tpatch int) {
 	mod.patch_len(tpatch)
 }
 
@@ -160,18 +156,14 @@ pub fn (mut mod Module) compile() []u8 {
 		{
 			mod.u32(u32(mod.fn_imports.len + mod.global_imports.len))
 			for ft in mod.fn_imports {
-				mod.u32(u32(ft.mod.len))
-				mod.buf << ft.mod.bytes()
-				mod.u32(u32(ft.name.len))
-				mod.buf << ft.name.bytes()
+				mod.name(ft.mod)
+				mod.name(ft.name)
 				mod.buf << 0x00 // function
 				mod.u32(u32(ft.tidx))
 			}
 			for gt in mod.global_imports {
-				mod.u32(u32(gt.mod.len))
-				mod.buf << gt.mod.bytes()
-				mod.u32(u32(gt.name.len))
-				mod.buf << gt.name.bytes()
+				mod.name(gt.mod)
+				mod.name(gt.name)
 				mod.buf << 0x03 // global
 				mod.global_type(gt.typ, gt.is_mut)
 			}
@@ -244,7 +236,7 @@ pub fn (mut mod Module) compile() []u8 {
 					continue
 				}
 				lsz++
-				mod.name(ft.name)
+				mod.name(ft.export_name or { ft.name })
 				mod.buf << 0x00 // function
 				mod.u32(u32(ft.idx + mod.fn_imports.len))
 			}

vlib/wasm/functions.v

@@ -43,4 +43,11 @@ mut:
 	locals  []FunctionLocal
 pub:
 	name string
+pub mut:
+	export_name ?string
+}
+
+// export_name sets the export name of the function to `name`
+pub fn (mut func Function) export_name(name string) {
+	func.export_name = name
 }

vlib/wasm/instructions.v

@@ -861,6 +861,17 @@ pub fn (mut func Function) cast_trapping(a NumType, is_signed bool, b NumType) {
 	func.cast(a, is_signed, b)
 }
 
+// reinterpret returns a value which has the same bit-pattern as its operand value, in its result type.
+// WebAssembly instruction: `f32.reinterpret_i32`, `i32.reinterpret_f32`, `f64.reinterpret_i64`, `i64.reinterpret_f64`.
+pub fn (mut func Function) reinterpret(a NumType) {
+	match a {
+		.f32_t { func.code << 0xBC } // i32.reinterpret_f32
+		.i32_t { func.code << 0xBE } // f32.reinterpret_i32
+		.f64_t { func.code << 0xBD } // i64.reinterpret_f64
+		.i64_t { func.code << 0xBF } // f64.reinterpret_i64
+	}
+}
+
 // unreachable denotes a point in code that should not be reachable, it is an unconditional trap.
 // WebAssembly instruction: `unreachable`.
 pub fn (mut func Function) unreachable() {
@@ -919,7 +930,7 @@ pub fn (mut func Function) c_return() {
 	func.code << 0x0F // return
 }
 
-// c_end ends the block or loop with the label passed in at `label`.
+// c_end ends the block, loop or if expression with the label passed in at `label`.
 pub fn (mut func Function) c_end(label LabelIndex) {
 	assert func.label == label, 'c_end: called with an invalid label ${label}'
 	func.label--
@@ -945,11 +956,6 @@ pub fn (mut func Function) c_br_if(label LabelIndex) {
 	func.u32(u32(v))
 }
 
-// c_end_if closes the current if expression.
-pub fn (mut func Function) c_end_if() {
-	func.code << 0x0B // END expression opcode
-}
-
 // call calls a locally defined function.
 // If this function does not exist when calling `compile` on the module, it will panic.
 // WebAssembly instruction: `call`.