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

.github/workflows/wasm_backend_tests_ci.yml

@@ -60,8 +60,10 @@ jobs:
       - name: Build V
         run: make -j4 && ./v symlink -githubci
 
-      - name: Install binaryen as build dependency for the V WASM backend
+      - name: Install wasmer to execute WASM modules
-        run: ./v cmd/tools/install_binaryen.vsh
+        run: |
+          curl https://get.wasmer.io -sSfL | sh
+          sudo ln -s ~/.wasmer/bin/wasmer /usr/local/bin
 
       - name: Build the V WASM backend
         run: ./v -cc clang -showcc -v cmd/tools/builders/wasm_builder.v
@@ -82,8 +84,10 @@ jobs:
       - name: Build V
         run: make -j4 && ./v symlink -githubci
 
-      - name: Install binaryen as build dependency for the V WASM backend
+      - name: Install wasmer to execute WASM modules
-        run: ./v cmd/tools/install_binaryen.vsh
+        run: |
+          curl https://get.wasmer.io -sSfL | sh
+          sudo ln -s ~/.wasmer/bin/wasmer /usr/local/bin
 
       - name: Build the V WASM backend
         run: ./v -cc clang -showcc -v cmd/tools/builders/wasm_builder.v
@@ -94,26 +98,26 @@ jobs:
       - name: Build examples
         run: VTEST_ONLY=wasm ./v build-examples
 
-  wasm-backend-windows:
+#  wasm-backend-windows:
-    runs-on: windows-2022
+#    runs-on: windows-2022
-    if: github.event_name != 'push' || github.event.ref == 'refs/heads/master' || github.event.repository.full_name != 'vlang/v'
+#    if: github.event_name != 'push' || github.event.ref == 'refs/heads/master' || github.event.repository.full_name != 'vlang/v'
-    timeout-minutes: 121
+#    timeout-minutes: 121
-    steps:
+#    steps:
-      - uses: actions/checkout@v3
+#      - uses: actions/checkout@v3
-
+#
-      - name: Build V
+#      - name: Build V
-        run: .\make.bat -msvc
+#        run: .\make.bat -msvc
-      - name: Symlink V
+#      - name: Symlink V
-        run: .\v.exe symlink -githubci
+#        run: .\v.exe symlink -githubci
-
+#
-      - name: Install binaryen as build dependency for the V WASM backend
+#      - name: Install binaryen as build dependency for the V WASM backend
-        run: v cmd/tools/install_binaryen.vsh
+#        run: v cmd/tools/install_binaryen.vsh
-
+#
-      - name: Build the V WASM backend
+#      - name: Build the V WASM backend
-        run: v -cc msvc -showcc -v cmd/tools/builders/wasm_builder.v
+#        run: v -cc msvc -showcc -v cmd/tools/builders/wasm_builder.v
-
+#
-      - name: Test the WASM backend
+#      - name: Test the WASM backend
-        run: v -stats test vlib/v/gen/wasm/tests/
+#        run: v -stats test vlib/v/gen/wasm/tests/
-
+#
-      - name: Build examples
+#      - name: Build examples
-        run: $env:VTEST_ONLY='wasm'; v build-examples
+#        run: $env:VTEST_ONLY='wasm'; v build-examples

.github/workflows/wasm_wabt_tests_ci.yml

@@ -1,73 +0,0 @@
-name: wasm wabt validate tests CI
-
-on:
-  push:
-    paths:
-      - '!**'
-      - '!**.md'
-      - 'vlib/builtin/**.v'
-      - 'vlib/wasm/**.v'
-      - 'vlib/wasm/tests/**.v'
-  pull_request:
-    paths:
-      - '!**'
-      - '!**.md'
-      - 'vlib/builtin/**.v'
-      - 'vlib/wasm/**.v'
-      - 'vlib/wasm/tests/**.v'
-
-concurrency:
-  group: wasm-wabt-ci-${{ github.event.pull_request.number || github.sha }}
-  cancel-in-progress: true
-
-jobs:
-  wasm-wabt-ubuntu:
-    runs-on: ubuntu-22.04
-    if: github.event_name != 'push' || github.event.ref == 'refs/heads/master' || github.event.repository.full_name != 'vlang/v'
-    timeout-minutes: 31
-    steps:
-      - uses: actions/checkout@v3
-
-      - name: Build V
-        run: make && ./v symlink -githubci
-
-      - name: Install wabt to get the wasm-validate executable
-        run: v cmd/tools/install_wabt.vsh
-
-      - name: Test the WASM backend
-        run: v test vlib/wasm/
-
-  wasm-wabt-macos:
-    runs-on: macOS-12
-    if: github.event_name != 'push' || github.event.ref == 'refs/heads/master' || github.event.repository.full_name != 'vlang/v'
-    timeout-minutes: 31
-    steps:
-      - uses: actions/checkout@v3
-
-      - name: Build V
-        run: make && ./v symlink -githubci
-
-      - name: Install wabt to get the wasm-validate executable
-        run: v cmd/tools/install_wabt.vsh
-
-      - name: Test the WASM backend
-        run: v test vlib/wasm/
-
-  wasm-wabt-windows:
-    runs-on: windows-2022
-    if: github.event_name != 'push' || github.event.ref == 'refs/heads/master' || github.event.repository.full_name != 'vlang/v'
-    timeout-minutes: 31
-    steps:
-      - uses: actions/checkout@v3
-
-      - name: Build V
-        run: .\make.bat -msvc
-
-      - name: Symlink V
-        run: .\v.exe symlink -githubci
-
-      - name: Install wabt to get the wasm-validate executable
-        run: v cmd/tools/install_wabt.vsh
-
-      - name: Test the WASM backend
-        run: v test vlib/wasm/

cmd/v/v.v

@@ -193,18 +193,7 @@ fn rebuild(prefs &pref.Preferences) {
 			util.launch_tool(prefs.is_verbose, 'builders/golang_builder', os.args[1..])
 		}
 		.wasm {
-			assert_wasm_backend_thirdparty()
 			util.launch_tool(prefs.is_verbose, 'builders/wasm_builder', os.args[1..])
 		}
 	}
 }
-
-fn assert_wasm_backend_thirdparty() {
-	vroot := os.dir(pref.vexe_path())
-	if !os.exists('${vroot}/cmd/tools/builders/wasm_builder')
-		&& !os.exists('${vroot}/thirdparty/binaryen') {
-		eprintln('The WebAssembly backend requires `binaryen`, an external library dependency')
-		eprintln('This can be installed with `./cmd/tools/install_binaryen.vsh`, to download prebuilt libraries for your platform')
-		exit(1)
-	}
-}

vlib/builtin/wasm/builtin.v

@@ -6,6 +6,20 @@ fn __memory_grow(size usize) usize
 fn __memory_fill(dest &u8, value isize, size isize)
 fn __memory_copy(dest &u8, src &u8, size isize)
 
+// add doc comments for the below functions
+
+// __reinterpret_f32_u32 converts a `u32` to a `f32` without changing the bit pattern.
+pub fn __reinterpret_f32_u32(v f32) u32
+
+// __reinterpret_u32_f32 converts a `f32` to a `u32` without changing the bit pattern.
+pub fn __reinterpret_u32_f32(v u32) f32
+
+// __reinterpret_f64_u64 converts a `u64` to a `f64` without changing the bit pattern.
+pub fn __reinterpret_f64_u64(v f64) u64
+
+// __reinterpret_u64_f64 converts a `f64` to a `u64` without changing the bit pattern.
+pub fn __reinterpret_u64_f64(v u64) f64
+
 // vcalloc dynamically allocates a zeroed `n` bytes block of memory on the heap.
 // vcalloc returns a `byteptr` pointing to the memory address of the allocated space.
 // Unlike `v_calloc` vcalloc checks for negative values given in `n`.

vlib/builtin/wasm/wasi/builtin.v

@@ -7,7 +7,7 @@ pub fn print(s string) {
 		len: usize(s.len)
 	}
 
-	WASM.fd_write(1, &elm, 1, -1)
+	WASM.fd_write(1, &elm, 1, 0)
 }
 
 // println prints a message with a line end, to stdout.
@@ -20,7 +20,7 @@ pub fn println(s string) {
 		len: 1
 	}]!
 
-	WASM.fd_write(1, &elm[0], 2, -1)
+	WASM.fd_write(1, &elm[0], 2, 0)
 }
 
 // eprint prints a message to stderr.
@@ -30,7 +30,7 @@ pub fn eprint(s string) {
 		len: usize(s.len)
 	}
 
-	WASM.fd_write(2, &elm, 1, -1)
+	WASM.fd_write(2, &elm, 1, 0)
 }
 
 // eprintln prints a message with a line end, to stderr.
@@ -43,7 +43,7 @@ pub fn eprintln(s string) {
 		len: 1
 	}]!
 
-	WASM.fd_write(2, &elm[0], 2, -1)
+	WASM.fd_write(2, &elm[0], 2, 0)
 }
 
 // exit terminates execution immediately and returns exit `code` to the shell.
@@ -57,6 +57,5 @@ pub fn exit(code int) {
 pub fn panic(s string) {
 	eprint('V panic: ')
 	eprintln(s)
-	_ := *&u8(-1)
 	exit(1)
 }

vlib/builtin/wasm/wasi/int.v

@@ -52,21 +52,18 @@ fn (nn int) str_l(max int) string {
 		}
 		diff := max - index
 		vmemmove(buf, voidptr(buf + index), diff + 1)
-		/*
-		// === manual memory move for bare metal ===
-		mut c:= 0
-		for c < diff {
-			buf[c] = buf[c+index]
-			c++
-		}
-		buf[c] = 0
-		*/
 		return tos(buf, diff)
 
 		// return tos(memdup(&buf[0] + index, (max - index)), (max - index))
 	}
 }
 
+// str returns the value of the `u8` as a `string`.
+// Example: assert u8(2).str() == '2'
+pub fn (n u8) str() string {
+	return int(n).str_l(5)
+}
+
 // str returns the value of the `i8` as a `string`.
 // Example: assert i8(-2).str() == '-2'
 pub fn (n i8) str() string {

vlib/builtin/wasm/wasi/wasi.v

@@ -1,4 +1,3 @@
-[wasm_import_namespace: 'wasi_snapshot_preview1']
 module builtin
 
 struct CIOVec {
@@ -9,6 +8,9 @@ struct CIOVec {
 type Errno = u16
 type FileDesc = int
 
+[wasm_import_namespace: 'wasi_snapshot_preview1']
 fn WASM.fd_write(fd FileDesc, iovs &CIOVec, iovs_len usize, retptr &usize) Errno
+
+[wasm_import_namespace: 'wasi_snapshot_preview1']
 [noreturn]
 fn WASM.proc_exit(rval int)

vlib/v/builder/compile.v

@@ -82,12 +82,44 @@ fn (mut b Builder) run_compiled_executable_and_exit() {
 	if !(b.pref.is_test || b.pref.is_run || b.pref.is_crun) {
 		exit(0)
 	}
-	compiled_file := os.real_path(b.pref.out_name)
+	mut compiled_file := b.pref.out_name
+	if b.pref.backend == .wasm && !compiled_file.ends_with('.wasm') {
+		compiled_file += '.wasm'
+	}
+	compiled_file = os.real_path(compiled_file)
+
+	mut run_args := []string{cap: b.pref.run_args.len + 1}
+
 	run_file := if b.pref.backend.is_js() {
 		node_basename := $if windows { 'node.exe' } $else { 'node' }
 		os.find_abs_path_of_executable(node_basename) or {
 			panic('Could not find `${node_basename}` in system path. Do you have Node.js installed?')
 		}
+	} else if b.pref.backend == .wasm {
+		mut actual_run := ['wasmer', 'wasmtime', 'wavm', 'wasm3']
+		mut actual_rf := ''
+
+		// -autofree bug
+		// error: cannot convert 'struct string' to 'struct _option_string'
+		// mut actual_rf := ?string(none)
+
+		for runtime in actual_run {
+			basename := $if windows { runtime + '.exe' } $else { runtime }
+
+			if rf := os.find_abs_path_of_executable(basename) {
+				if basename == 'wavm' {
+					run_args << 'run'
+				}
+				actual_rf = rf
+				break
+			}
+		}
+
+		if actual_rf == '' {
+			panic('Could not find `wasmer`, `wasmtime`, `wavm`, or `wasm3` in system path. Do you have any installed?')
+		}
+
+		actual_rf
 	} else if b.pref.backend == .golang {
 		go_basename := $if windows { 'go.exe' } $else { 'go' }
 		os.find_abs_path_of_executable(go_basename) or {
@@ -96,8 +128,7 @@ fn (mut b Builder) run_compiled_executable_and_exit() {
 	} else {
 		compiled_file
 	}
-	mut run_args := []string{cap: b.pref.run_args.len + 1}
+	if b.pref.backend.is_js() || b.pref.backend == .wasm {
-	if b.pref.backend.is_js() {
 		run_args << compiled_file
 	} else if b.pref.backend == .golang {
 		run_args << ['run', compiled_file]

vlib/v/gen/wasm/cast.v

@@ -1,91 +0,0 @@
-module wasm
-
-import v.ast
-import v.gen.wasm.binaryen
-
-fn (mut g Gen) is_signed(typ ast.Type) bool {
-	if typ.is_pure_float() {
-		return true
-	}
-	return typ.is_signed()
-}
-
-fn (mut g Gen) unary_cast(from binaryen.Type, is_signed bool, to binaryen.Type) binaryen.Op {
-	if is_signed {
-		match from {
-			type_i32 {
-				match to {
-					type_i64 { return binaryen.extendsint32() }
-					type_f32 { return binaryen.convertsint32tofloat32() }
-					type_f64 { return binaryen.convertsint32tofloat64() }
-					else {}
-				}
-			}
-			type_i64 {
-				match to {
-					type_i32 { return binaryen.wrapint64() }
-					type_f32 { return binaryen.convertsint64tofloat32() }
-					type_f64 { return binaryen.convertsint64tofloat64() }
-					else {}
-				}
-			}
-			type_f32 {
-				match to {
-					type_i32 { return binaryen.truncsfloat32toint32() }
-					type_i64 { return binaryen.truncsfloat32toint64() }
-					type_f64 { return binaryen.promotefloat32() }
-					else {}
-				}
-			}
-			type_f64 {
-				match to {
-					type_i32 { return binaryen.truncsfloat64toint32() }
-					type_i64 { return binaryen.truncsfloat64toint64() }
-					type_f32 { return binaryen.demotefloat64() }
-					else {}
-				}
-			}
-			else {}
-		}
-	} else {
-		match from {
-			type_i32 {
-				match to {
-					type_i64 { return binaryen.extenduint32() }
-					type_f32 { return binaryen.convertuint32tofloat32() }
-					type_f64 { return binaryen.convertuint32tofloat64() }
-					else {}
-				}
-			}
-			type_i64 {
-				match to {
-					type_i32 { return binaryen.wrapint64() }
-					type_f32 { return binaryen.convertuint64tofloat32() }
-					type_f64 { return binaryen.convertuint64tofloat64() }
-					else {}
-				}
-			}
-			else {}
-		}
-	}
-	g.w_error('bad cast: from ${from} (is signed: ${is_signed}) to ${to}')
-}
-
-fn (mut g Gen) cast_t(expr binaryen.Expression, from ast.Type, to ast.Type) binaryen.Expression {
-	return g.cast(expr, g.get_wasm_type(from), g.is_signed(from), g.get_wasm_type(to))
-}
-
-fn (mut g Gen) cast(expr binaryen.Expression, from binaryen.Type, is_signed bool, to binaryen.Type) binaryen.Expression {
-	if from == to {
-		return expr
-	}
-
-	// In the official spec, integers are represented in twos complement.
-	// WebAssembly does not keep signedness information in it's types
-	// and uses instructions with variants for signed or unsigned values.
-	//
-	// You only need to know if the original type is signed or not to
-	// perform casting.
-
-	return binaryen.unary(g.mod, g.unary_cast(from, is_signed, to), expr)
-}

vlib/v/gen/wasm/ops.v

@@ -1,69 +1,73 @@
+// Copyright (c) 2023 l-m.dev. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
 module wasm
 
 import v.ast
 import v.token
-import v.gen.wasm.binaryen
+import wasm
 
-const (
+pub fn (mut g Gen) as_numtype(a wasm.ValType) wasm.NumType {
-	type_none = binaryen.typenone()
+	if a in [.funcref_t, .externref_t, .v128_t] {
-	type_auto = binaryen.typeauto()
+		g.w_error("as_numtype: called with '${a}'")
-	type_i32  = binaryen.typeint32()
+	}
-	type_i64  = binaryen.typeint64()
+
-	type_f32  = binaryen.typefloat32()
+	return unsafe { wasm.NumType(a) }
-	type_f64  = binaryen.typefloat64()
+}
-)
+
+// unwraps int_literal to i64_t
+pub fn (mut g Gen) get_wasm_type_int_literal(typ_ ast.Type) wasm.ValType {
+	if typ_ == ast.int_literal_type_idx {
+		return wasm.ValType.i64_t
+	}
+	return g.get_wasm_type(typ_)
+}
 
 // "Register size" types such as int, i64 and bool boil down to their WASM counterparts.
 // Structures and unions are pointers, i32.
-fn (mut g Gen) get_wasm_type(typ_ ast.Type) binaryen.Type {
+pub fn (mut g Gen) get_wasm_type(typ_ ast.Type) wasm.ValType {
 	typ := ast.mktyp(typ_)
 	if typ == ast.void_type_idx {
-		return wasm.type_none
+		g.w_error("get_wasm_type: called with 'void'")
 	}
-	if typ.is_any_kind_of_pointer() {
+	if typ.is_ptr() || typ.is_pointer() {
-		g.needs_stack = true
+		return wasm.ValType.i32_t
-		return wasm.type_i32
 	}
 	if typ in ast.number_type_idxs {
 		return match typ {
 			ast.isize_type_idx, ast.usize_type_idx, ast.i8_type_idx, ast.u8_type_idx,
 			ast.char_type_idx, ast.rune_type_idx, ast.i16_type_idx, ast.u16_type_idx,
 			ast.int_type_idx, ast.u32_type_idx {
-				wasm.type_i32
+				wasm.ValType.i32_t
 			}
-			ast.i64_type_idx, ast.u64_type_idx, ast.int_literal_type_idx {
+			ast.i64_type_idx, ast.u64_type_idx {
-				wasm.type_i64
+				wasm.ValType.i64_t
 			}
 			ast.f32_type_idx {
-				wasm.type_f32
+				wasm.ValType.f32_t
 			}
-			ast.f64_type_idx, ast.float_literal_type_idx {
+			ast.f64_type_idx {
-				wasm.type_f64
+				wasm.ValType.f64_t
 			}
 			else {
-				wasm.type_i32
+				wasm.ValType.i32_t
 			}
 		}
 	}
 	if typ == ast.bool_type_idx {
-		return wasm.type_i32
+		return wasm.ValType.i32_t
 	}
 	ts := g.table.sym(typ)
 	match ts.info {
 		ast.Struct {
-			g.get_type_size_align(typ)
+			g.pool.type_size(typ)
-			return wasm.type_i32 // pointer
+			return wasm.ValType.i32_t // pointer
-		}
-		ast.MultiReturn {
-			// TODO: cache??
-			mut paraml := ts.info.types.map(g.get_wasm_type(it))
-			return binaryen.typecreate(paraml.data, paraml.len)
 		}
 		ast.Alias {
 			return g.get_wasm_type(ts.info.parent_type)
 		}
 		ast.ArrayFixed {
-			return wasm.type_i32
+			return wasm.ValType.i32_t // pointer
 		}
 		ast.Enum {
 			return g.get_wasm_type(ts.info.typ)
@@ -74,251 +78,68 @@ fn (mut g Gen) get_wasm_type(typ_ ast.Type) binaryen.Type {
 	g.w_error("get_wasm_type: unreachable type '${*g.table.sym(typ)}' ${ts.info}")
 }
 
-fn infix_kind_return_bool(op token.Kind) bool {
+pub fn (mut g Gen) infix_from_typ(typ ast.Type, op token.Kind) {
-	return op in [.eq, .ne, .gt, .lt, .ge, .le]
+	if g.is_param_type(typ) {
+		eprintln(*g.table.sym(typ))
+		panic('unimplemented')
 	}
 
-fn (mut g Gen) infix_from_typ(typ ast.Type, op token.Kind) binaryen.Op {
+	wasm_typ := g.as_numtype(g.get_wasm_type(typ))
-	wasm_typ := g.get_wasm_type(typ)
 
-	match wasm_typ {
-		wasm.type_i32 {
 	match op {
 		.plus {
-					return binaryen.addint32()
+			g.func.add(wasm_typ)
 		}
 		.minus {
-					return binaryen.subint32()
+			g.func.sub(wasm_typ)
 		}
 		.mul {
-					return binaryen.mulint32()
+			g.func.mul(wasm_typ)
 		}
 		.mod {
-					if typ.is_signed() {
+			g.func.rem(wasm_typ, typ.is_signed())
-						return binaryen.remsint32()
-					} else {
-						return binaryen.remuint32()
-					}
 		}
 		.div {
-					if typ.is_signed() {
+			g.func.div(wasm_typ, typ.is_signed())
-						return binaryen.divsint32()
-					} else {
-						return binaryen.divuint32()
-					}
 		}
 		.eq {
-					return binaryen.eqint32()
+			g.func.eq(wasm_typ)
 		}
 		.ne {
-					return binaryen.neint32()
+			g.func.ne(wasm_typ)
 		}
 		.gt {
-					if typ.is_signed() {
+			g.func.gt(wasm_typ, typ.is_signed())
-						return binaryen.gtsint32()
-					} else {
-						return binaryen.gtuint32()
-					}
 		}
 		.lt {
-					if typ.is_signed() {
+			g.func.lt(wasm_typ, typ.is_signed())
-						return binaryen.ltsint32()
-					} else {
-						return binaryen.ltuint32()
-					}
 		}
 		.ge {
-					if typ.is_signed() {
+			g.func.ge(wasm_typ, typ.is_signed())
-						return binaryen.gesint32()
-					} else {
-						return binaryen.geuint32()
-					}
 		}
 		.le {
-					if typ.is_signed() {
+			g.func.le(wasm_typ, typ.is_signed())
-						return binaryen.lesint32()
-					} else {
-						return binaryen.leuint32()
 		}
-				}
-				/*.logical_or {
-					return binaryen.orint32() // TODO: logical or
-				}*/
 		.xor {
-					return binaryen.xorint32()
+			g.func.b_xor(wasm_typ)
 		}
 		.pipe {
-					return binaryen.orint32()
+			g.func.b_or(wasm_typ)
 		}
 		.amp {
-					return binaryen.andint32()
+			g.func.b_and(wasm_typ)
 		}
 		.left_shift {
-					return binaryen.shlint32()
+			g.func.b_shl(wasm_typ)
 		}
 		.right_shift {
-					return binaryen.shrsint32()
+			g.func.b_shr(wasm_typ, true)
 		}
 		.unsigned_right_shift {
-					return binaryen.shruint32()
+			g.func.b_shr(wasm_typ, false)
-				}
-				else {}
-			}
-		}
-		wasm.type_i64 {
-			match op {
-				.plus {
-					return binaryen.addint64()
-				}
-				.minus {
-					return binaryen.subint64()
-				}
-				.mul {
-					return binaryen.mulint64()
-				}
-				.mod {
-					if typ.is_signed() {
-						return binaryen.remsint64()
-					} else {
-						return binaryen.remuint64()
-					}
-				}
-				.div {
-					if typ.is_signed() {
-						return binaryen.divsint64()
-					} else {
-						return binaryen.divuint64()
-					}
-				}
-				.eq {
-					return binaryen.eqint64()
-				}
-				.ne {
-					return binaryen.neint64()
-				}
-				.gt {
-					if typ.is_signed() {
-						return binaryen.gtsint64()
-					} else {
-						return binaryen.gtuint64()
-					}
-				}
-				.lt {
-					if typ.is_signed() {
-						return binaryen.ltsint64()
-					} else {
-						return binaryen.ltuint64()
-					}
-				}
-				.ge {
-					if typ.is_signed() {
-						return binaryen.gesint64()
-					} else {
-						return binaryen.geuint64()
-					}
-				}
-				.le {
-					if typ.is_signed() {
-						return binaryen.lesint64()
-					} else {
-						return binaryen.leuint64()
-					}
-				}
-				/*.logical_or {
-					return binaryen.orint64() // TODO: logical or
-				}*/
-				.xor {
-					return binaryen.xorint64()
-				}
-				.pipe {
-					return binaryen.orint64()
-				}
-				.amp {
-					return binaryen.andint64()
-				}
-				.left_shift {
-					return binaryen.shlint64()
-				}
-				.right_shift {
-					return binaryen.shrsint64()
-				}
-				.unsigned_right_shift {
-					return binaryen.shruint64()
-				}
-				else {}
-			}
-		}
-		wasm.type_f32 {
-			match op {
-				.plus {
-					return binaryen.addfloat32()
-				}
-				.minus {
-					return binaryen.subfloat32()
-				}
-				.mul {
-					return binaryen.mulfloat32()
-				}
-				.div {
-					return binaryen.divfloat32()
-				}
-				.eq {
-					return binaryen.eqfloat32()
-				}
-				.ne {
-					return binaryen.nefloat32()
-				}
-				.gt {
-					return binaryen.gtfloat32()
-				}
-				.lt {
-					return binaryen.ltfloat32()
-				}
-				.ge {
-					return binaryen.gefloat32()
-				}
-				.le {
-					return binaryen.lefloat32()
-				}
-				else {}
-			}
-		}
-		wasm.type_f64 {
-			match op {
-				.plus {
-					return binaryen.addfloat64()
-				}
-				.minus {
-					return binaryen.subfloat64()
-				}
-				.mul {
-					return binaryen.mulfloat64()
-				}
-				.div {
-					return binaryen.divfloat64()
-				}
-				.eq {
-					return binaryen.eqfloat64()
-				}
-				.ne {
-					return binaryen.nefloat64()
-				}
-				.gt {
-					return binaryen.gtfloat64()
-				}
-				.lt {
-					return binaryen.ltfloat64()
-				}
-				.ge {
-					return binaryen.gefloat64()
-				}
-				.le {
-					return binaryen.lefloat64()
-				}
-				else {}
-			}
-		}
-		else {}
 		}
+		else {
 			g.w_error('bad infix: op `${op}`')
 		}
+	}
+}

vlib/v/gen/wasm/serialisation.v

@@ -1,168 +0,0 @@
-module wasm
-
-import v.ast
-import v.gen.wasm.binaryen
-import encoding.binary as bin
-import math.bits
-
-fn (mut g Gen) bake_constants_plus_initialisers() []GlobalData {
-	mut initialisers := []GlobalData{}
-
-	for _, global in g.globals {
-		match global.init {
-			/*
-			ast.ArrayInit {
-				// TODO: call a seraliser recursively over all elements
-				
-				if !global.init.is_fixed {
-					g.w_error('wasm backend does not support non fixed arrays yet')
-				}
-				for global.init
-			}*/
-			ast.BoolLiteral {
-				g.constant_data << ConstantData{
-					offset: global.abs_address
-					data: [u8(global.init.val)]
-				}
-			}
-			ast.FloatLiteral {
-				mut buf := []u8{len: 8}
-				wtyp := g.get_wasm_type(global.ast_typ)
-				match wtyp {
-					type_f32 {
-						bin.little_endian_put_u32(mut buf, bits.f32_bits(global.init.val.f32()))
-					}
-					type_f64 {
-						bin.little_endian_put_u64(mut buf, bits.f64_bits(global.init.val.f64()))
-						unsafe {
-							buf.len = 4
-						}
-					}
-					else {}
-				}
-
-				g.constant_data << ConstantData{
-					offset: global.abs_address
-					data: buf
-				}
-			}
-			ast.StringLiteral {
-				offset, len := g.allocate_string(global.init)
-
-				if g.table.sym(global.ast_typ).info !is ast.Struct {
-					mut buf := []u8{len: 4}
-					bin.little_endian_put_u32(mut buf, u32(offset))
-					g.constant_data << ConstantData{
-						offset: global.abs_address
-						data: buf
-					}
-				} else {
-					mut buf := []u8{len: 8}
-					bin.little_endian_put_u32(mut buf, u32(offset))
-					bin.little_endian_put_u32_at(mut buf, u32(len), 4)
-
-					g.constant_data << ConstantData{
-						offset: global.abs_address
-						data: buf
-					}
-				}
-			}
-			ast.IntegerLiteral {
-				mut buf := []u8{len: 8}
-				wtyp := g.get_wasm_type(global.ast_typ)
-				match wtyp {
-					type_i32 {
-						bin.little_endian_put_u32(mut buf, u32(global.init.val.int()))
-					}
-					type_i64 {
-						bin.little_endian_put_u64(mut buf, u64(global.init.val.i64()))
-						unsafe {
-							buf.len = 4
-						}
-					}
-					else {}
-				}
-
-				g.constant_data << ConstantData{
-					offset: global.abs_address
-					data: buf
-				}
-			}
-			else {
-				initialisers << global
-			}
-		}
-	}
-
-	return initialisers
-}
-
-fn round_up_to_multiple(val int, multiple int) int {
-	return val + (multiple - val % multiple) % multiple
-}
-
-fn (mut g Gen) make_vinit() binaryen.Function {
-	runtime_inits := g.bake_constants_plus_initialisers()
-
-	g.bare_function_start()
-
-	mut body := runtime_inits.map(g.set_var_v(it.to_var(''), g.expr(it.init, it.ast_typ)))
-
-	for mod_name in g.table.modules {
-		if mod_name == 'v.reflection' {
-			g.w_error('the wasm backend does not implement `v.reflection` yet')
-		}
-
-		init_fn_name := if mod_name != 'builtin' { '${mod_name}.init' } else { 'init' }
-		if _ := g.table.find_fn(init_fn_name) {
-			body << binaryen.call(g.mod, init_fn_name.str, unsafe { nil }, 0, type_none)
-		}
-		cleanup_fn_name := if mod_name != 'builtin' { '${mod_name}.cleanup' } else { 'cleanup' }
-		if _ := g.table.find_fn(cleanup_fn_name) {
-			body << binaryen.call(g.mod, cleanup_fn_name.str, unsafe { nil }, 0, type_none)
-		}
-	}
-
-	return g.bare_function('_vinit', g.mkblock(body))
-}
-
-fn (mut g Gen) housekeeping() {
-	// `_vinit` should be used to initialise the WASM module,
-	// then `main.main` can be called safely.
-	vinit := g.make_vinit()
-	stack_base := round_up_to_multiple(g.constant_data_offset, 1024)
-	heap_base := if g.needs_stack {
-		stack_base + 1024 * 16 // 16KiB of stack
-	} else {
-		stack_base
-	}
-	pages_needed := heap_base / (1024 * 64) + 1
-
-	if g.needs_stack || g.constant_data.len != 0 {
-		data := g.constant_data.map(it.data.data)
-		data_len := g.constant_data.map(it.data.len)
-		data_offsets := g.constant_data.map(binaryen.constant(g.mod, binaryen.literalint32(it.offset)))
-		passive := []bool{len: g.constant_data.len, init: false}
-
-		binaryen.setmemory(g.mod, pages_needed, pages_needed + 4, c'memory', data.data,
-			passive.data, data_offsets.data, data_len.data, data.len, false, false, c'memory')
-		binaryen.addglobal(g.mod, c'__heap_base', type_i32, false, g.literalint(heap_base,
-			ast.int_type))
-	}
-	if g.needs_stack {
-		// `g.constant_data_offset` rounded up to a multiple of 1024
-		binaryen.addglobal(g.mod, c'__vsp', type_i32, true, g.literalint(stack_base, ast.int_type))
-	}
-	if g.pref.os == .wasi {
-		main_expr := g.mkblock([binaryen.call(g.mod, c'_vinit', unsafe { nil }, 0, type_none),
-			binaryen.call(g.mod, c'main.main', unsafe { nil }, 0, type_none)])
-		binaryen.addfunction(g.mod, c'_start', type_none, type_none, unsafe { nil }, 0,
-			main_expr)
-		binaryen.addfunctionexport(g.mod, c'_start', c'_start')
-	} else {
-		// In `browser` mode, and function can be exported and called regardless.
-		// To avoid uninitialised data, `_vinit` is set to be ran immediately on
-		// WASM module creation.
-		binaryen.setstart(g.mod, vinit)
-	}
-}

vlib/v/gen/wasm/serialise/alignment_test.v

@@ -0,0 +1,12 @@
+import v.ast
+import v.gen.wasm.serialise
+
+fn test_alignment() {
+	table := ast.new_table()
+
+	mut pool := serialise.new_pool(table)
+	pool.append(ast.BoolLiteral{ val: true }, 0) // +0, +1
+	pool.append(ast.FloatLiteral{ val: '0' }, ast.f32_type) // +3, +4
+	pool.append(ast.BoolLiteral{ val: true }, 0) // +0, +1
+	assert pool.buf.len == 9
+}

vlib/v/gen/wasm/serialise/serialise.v

@@ -0,0 +1,449 @@
+// Copyright (c) 2023 l-m.dev. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module serialise
+
+import v.ast
+// import v.eval
+import math.bits
+import strconv
+
+[noinit]
+pub struct Pool {
+mut:
+	table &ast.Table
+	// eval    eval.Eval
+	structs map[ast.Type]StructInfo
+	strings []StringInfo // string intern
+pub:
+	null_terminated bool
+	intern_strings  bool
+	store_relocs    bool
+pub mut:
+	buf               []u8
+	relocs            []Reloc
+	highest_alignment int
+}
+
+struct StringInfo {
+	pos int
+	len int
+}
+
+pub struct StructInfo {
+pub mut:
+	offsets []int
+}
+
+pub struct Reloc {
+pub:
+	pos    int
+	offset int
+}
+
+pub fn (mut p Pool) type_struct_info(typ ast.Type) ?StructInfo {
+	ts := p.table.sym(typ)
+
+	if ts.info !is ast.Struct {
+		return none
+	}
+
+	if typ.idx() in p.structs {
+		return p.structs[typ.idx()]
+	}
+
+	// will cache inside `p.structs`
+	p.type_size(typ)
+	return p.structs[typ.idx()]
+}
+
+pub fn (mut p Pool) type_size(typ ast.Type) (int, int) {
+	ts := p.table.sym(typ)
+	if ts.size != -1 && typ.idx() in p.structs {
+		return ts.size, ts.align
+	}
+
+	if ts.info is ast.Enum {
+		return p.table.type_size(ts.info.typ)
+	}
+
+	if ts.info !is ast.Struct {
+		return p.table.type_size(typ)
+	}
+
+	ti := ts.info as ast.Struct
+
+	// code borrowed from native, inserted in wasm, and now here!
+
+	mut strc := StructInfo{}
+	mut size := 0
+	mut align := 1
+	for f in ti.fields {
+		f_size, f_align := p.type_size(f.typ)
+		if f_size == 0 {
+			strc.offsets << 0
+			continue
+		}
+		padding := (f_align - size % f_align) % f_align
+		strc.offsets << size + padding
+		size += f_size + padding
+		if f_align > align {
+			align = f_align
+		}
+	}
+	size = (size + align - 1) / align * align
+	p.structs[typ.idx()] = strc
+
+	mut ts_ := p.table.sym(typ)
+	ts_.size = size
+	ts_.align = align
+
+	return size, align
+}
+
+[params]
+pub struct PoolOpts {
+	null_terminated bool = true
+	intern_strings  bool = true
+	store_relocs    bool = true
+}
+
+pub fn new_pool(table &ast.Table, opts PoolOpts) Pool {
+	return Pool{
+		table: table
+		null_terminated: opts.null_terminated
+		intern_strings: opts.intern_strings
+		store_relocs: opts.store_relocs
+	}
+}
+
+fn (mut p Pool) zero_fill(size int) {
+	// TODO: eventually support a way to utilise a BSS section
+
+	for i := 0; i < size; i++ {
+		p.buf << 0
+	}
+}
+
+fn (mut p Pool) alignment(align int) int {
+	if align > p.highest_alignment {
+		p.highest_alignment = align
+	}
+	padding := (align - p.buf.len % align) % align
+	p.zero_fill(padding)
+	pos := p.buf.len
+	return pos
+}
+
+/*
+fn (mut p Pool) append_struct(init ast.StructInit) ?int {
+	old_len := p.buf.len
+
+	size, align := p.type_size(v.typ)
+	ts := g.table.sym(v.typ)
+	ts_info := ts.info as ast.Struct
+
+	pos := p.alignment(align)
+	
+	if init.fields.len == 0 && !(ts_info.fields.any(it.has_default_expr)) {
+		for i := 0 ; i < size ; i++ {
+			p.buf << 0
+		}
+		return pos
+	}
+
+	/* for i, f in ts_info.fields {
+		field_to_be_set := init.fields.map(it.name).filter(f.name)
+	} */
+
+	/* for i, f in ts_info.fields {
+		field_to_be_set := init.fields.map(it.name).contains(f.name)
+
+		if !field_to_be_set {
+			offset := g.structs[v.typ.idx()].offsets[i]
+			offset_var := g.offset(v, f.typ, offset)
+
+			fsize, _ := g.get_type_size_align(f.typ)
+			
+			if f.has_default_expr {
+				g.expr(f.default_expr, f.typ)
+				g.set(offset_var)
+			} else {
+				g.zero_fill(offset_var, fsize)
+			}						
+		}
+	}
+
+	for f in init.fields {
+		field := ts.find_field(f.name) or {
+			g.w_error('could not find field `${f.name}` on init')
+		}
+		
+		offset := g.structs[v.typ.idx()].offsets[field.i]
+		offset_var := g.offset(v, f.expected_type, offset)
+
+		g.expr(f.expr, f.expected_type)
+		g.set(offset_var)
+	} */
+
+	return pos
+}*/
+
+pub fn eval_escape_codes_raw(str string) !string {
+	mut buffer := []u8{}
+
+	mut i := 0
+	for i < str.len {
+		if str[i] != `\\` {
+			buffer << str[i]
+			i++
+			continue
+		}
+
+		// skip \
+		i++
+		match str[i] {
+			`\\`, `'`, `"` {
+				buffer << str[i]
+				i++
+			}
+			`a`, `b`, `f` {
+				buffer << str[i] - u8(90)
+				i++
+			}
+			`n` {
+				buffer << `\n`
+				i++
+			}
+			`r` {
+				buffer << `\r`
+				i++
+			}
+			`t` {
+				buffer << `\t`
+				i++
+			}
+			`u` {
+				i++
+				utf8 := strconv.parse_int(str[i..i + 4], 16, 16) or {
+					return error('invalid \\u escape code (${str[i..i + 4]})')
+				}
+				i += 4
+				buffer << u8(utf8)
+				buffer << u8(utf8 >> 8)
+			}
+			`v` {
+				buffer << `\v`
+				i++
+			}
+			`x` {
+				i++
+				c := strconv.parse_int(str[i..i + 2], 16, 8) or {
+					return error('invalid \\x escape code (${str[i..i + 2]})')
+				}
+				i += 2
+				buffer << u8(c)
+			}
+			`0`...`7` {
+				c := strconv.parse_int(str[i..i + 3], 8, 8) or {
+					return error('invalid escape code \\${str[i..i + 3]}')
+				}
+				i += 3
+				buffer << u8(c)
+			}
+			else {
+				return error('invalid escape code \\${str[i]}')
+			}
+		}
+	}
+
+	return buffer.bytestr()
+}
+
+pub fn eval_escape_codes(str_lit ast.StringLiteral) !string {
+	if str_lit.is_raw {
+		return str_lit.val
+	}
+
+	return eval_escape_codes_raw(str_lit.val)
+}
+
+pub fn (mut p Pool) append_string(val string) int {
+	data := val.bytes()
+
+	if p.intern_strings {
+		for str in p.strings {
+			if data.len > str.len || (p.null_terminated && data.len != str.len) {
+				continue
+			}
+
+			// TODO: aggressive string interning if `p.null_terminated`
+			if p.buf[str.pos..str.pos + data.len] == data {
+				return str.pos
+			}
+		}
+	}
+
+	pos := p.buf.len
+	p.buf << data
+	if p.null_terminated {
+		p.buf << 0
+	}
+
+	p.strings << StringInfo{
+		pos: pos
+		len: data.len
+	}
+
+	return pos
+}
+
+pub fn (mut p Pool) append(init ast.Expr, typ ast.Type) (int, bool) {
+	match init {
+		ast.BoolLiteral {
+			pos := p.buf.len
+			p.buf << u8(init.val)
+			return pos, true
+		}
+		ast.FloatLiteral {
+			assert typ.is_pure_float()
+
+			mut pos := 0
+			if typ == ast.f32_type {
+				pos = p.alignment(4)
+				p.u32(bits.f32_bits(init.val.f32()))
+			} else {
+				pos = p.alignment(8)
+				p.u64(bits.f64_bits(init.val.f64()))
+			}
+
+			return pos, true
+		}
+		ast.IntegerLiteral {
+			assert typ.is_pure_int()
+
+			size, align := p.table.type_size(typ)
+			pos := p.alignment(align)
+
+			match size {
+				1 {
+					p.u8(u8(init.val.i8()))
+				}
+				2 {
+					p.u16(u16(init.val.i16()))
+				}
+				4 {
+					p.u32(u32(init.val.int()))
+				}
+				8 {
+					p.u64(u64(init.val.i64()))
+				}
+				else {}
+			}
+
+			return pos, true
+		}
+		ast.CharLiteral {
+			// 3 extra bytes for improved program correctness, thank me later
+			rne := u32(eval_escape_codes_raw(init.val) or { panic('Pool.append: ${err}') }.runes()[0])
+			pos := p.alignment(4)
+			p.u32(rne)
+
+			return pos, true
+		}
+		ast.StringLiteral {
+			val := eval_escape_codes(init) or { panic('Pool.append: ${err}') }
+			str_pos := p.append_string(val)
+
+			if typ != ast.string_type {
+				// c'str'
+				return str_pos, true
+			}
+
+			_, align := p.type_size(ast.string_type)
+			tss := p.table.sym(ast.string_type).info as ast.Struct
+			pos := p.alignment(align)
+
+			for field in tss.fields {
+				match field.name {
+					'str' {
+						p.ptr(str_pos)
+					}
+					'len' {
+						p.u32(u32(val.len))
+					}
+					'is_lit' {
+						p.u32(1)
+					}
+					else {
+						panic('ast.string: field `${field.name}` is unknown')
+					}
+				}
+			}
+
+			return pos, true
+		}
+		else {
+			size, align := p.type_size(typ)
+			pos := p.alignment(align)
+			p.zero_fill(size)
+			return pos, false
+		}
+	}
+}
+
+fn (mut p Pool) u64(v u64) {
+	p.buf << u8(v)
+	p.buf << u8(v >> u64(8))
+	p.buf << u8(v >> u64(16))
+	p.buf << u8(v >> u64(24))
+	p.buf << u8(v >> u64(32))
+	p.buf << u8(v >> u64(40))
+	p.buf << u8(v >> u64(48))
+	p.buf << u8(v >> u64(56))
+}
+
+fn (mut p Pool) u32(v u32) {
+	p.buf << u8(v)
+	p.buf << u8(v >> u32(8))
+	p.buf << u8(v >> u32(16))
+	p.buf << u8(v >> u32(24))
+}
+
+fn (mut p Pool) u16(v u16) {
+	p.buf << u8(v)
+	p.buf << u8(v >> u32(8))
+}
+
+fn (mut p Pool) u8(v u8) {
+	p.buf << v
+}
+
+fn (mut p Pool) ptr(offset int) int {
+	assert p.table.pointer_size in [1, 2, 4, 8]
+	pos := p.buf.len // p.alignment(p.table.pointer_size)
+
+	if p.store_relocs {
+		p.relocs << Reloc{
+			pos: pos
+			offset: offset
+		}
+	}
+
+	match p.table.pointer_size {
+		1 {
+			p.u8(u8(offset))
+		}
+		2 {
+			p.u16(u16(offset))
+		}
+		4 {
+			p.u32(u32(offset))
+		}
+		8 {
+			p.u64(u64(offset))
+		}
+		else {}
+	}
+	return pos
+}

vlib/v/gen/wasm/tests/arith.vv

@@ -84,3 +84,60 @@ pub fn powi(a i64, b i64) i64 {
 
 	return v
 }
+
+pub fn sqrti(a i64) i64 {
+	mut x := a
+	mut q, mut r := i64(1), i64(0)
+	for ; q <= x; {
+		q <<= 2
+	}
+	for ; q > 1; {
+		q >>= 2
+		t := x - r - q
+		r >>= 1
+		if t >= 0 {
+			x = t
+			r += q
+		}
+	}
+	return r
+}
+
+fn main() {
+	println('--- test printing numbers')
+	println(-20)
+	println(0)
+	println(22)
+	println(-1000000022)
+
+	println('--- test powi')
+	println(powi(2, 62))
+	println(powi(0, -2))
+	println(powi(2, -1))
+
+	println('--- test sqrti')
+	println(sqrti(i64(123456789) * i64(123456789)))
+	println(sqrti(144))
+	println(sqrti(0))
+
+	println('--- test negate')
+	println(negate(20))
+	println(negate(-1))
+
+	println('--- test inc')
+	println(inc(20))
+	println(inc(-1))
+
+	println('--- test lcm')
+	println(lcm(2, 3))
+	println(lcm(-2, 3))
+	println(lcm(-2, -3))
+	println(lcm(0, 0))
+
+	println('--- test gcd')
+
+	println(gcd(6, 9))
+	println(gcd(6, -9))
+	println(gcd(-6, -9))
+	println(gcd(0, 0))
+}

vlib/v/gen/wasm/tests/arith.vv.out

@@ -0,0 +1,29 @@
+--- test printing numbers
+-20
+0
+22
+-1000000022
+--- test powi
+4611686018427387904
+-1
+0
+--- test sqrti
+123456789
+12
+0
+--- test negate
+-20
+1
+--- test inc
+20
+-1
+--- test lcm
+6
+6
+6
+0
+--- test gcd
+3
+3
+3
+0

vlib/v/gen/wasm/tests/arrays.vv

@@ -3,12 +3,14 @@ struct TEST {
 	b i64
 }
 
-fn static_arrays() {
+fn static_arrays() (int, int, i64) {
 	a := [8]int{}
 	b := [10, 12, 150]!
 	c := [TEST{}, TEST{
 		b: 10
 	}]!
+
+	return a[2], b[1], c[1].b
 }
 
 fn index_expression() {
@@ -16,7 +18,11 @@ fn index_expression() {
 
 	a := b[2]
 	c := 'hello'[4]
-	d := c'hello'[2]
+	d := unsafe { c'hello'[2] }
+
+	println(a)
+	println(c)
+	println(d)
 }
 
 fn test_this(index int) int {
@@ -31,9 +37,31 @@ struct AA {
 	a [10]&int
 }
 
-fn main() {
+fn test_stuff() &int {
 	a := AA{}
 
 	mut b := &int(0)
 	b = a.a[2]
+
+	return b
+}
+
+fn main() {
+	println('--- static_arrays()')
+	a, b, c := static_arrays()
+	println(a)
+	println(b)
+	println(c)
+
+	println('--- index_expression()')
+	index_expression()
+
+	println('--- test_this()')
+	println(test_this(2))
+	println(test_this(10))
+	println(test_this(-1))
+
+	println('--- test_stuff()')
+	v := test_stuff()
+	println(v)
 }

vlib/v/gen/wasm/tests/arrays.vv.out

@@ -0,0 +1,14 @@
+--- static_arrays()
+0
+12
+10
+--- index_expression()
+150
+111
+108
+--- test_this()
+108
+10
+10
+--- test_stuff()
+0

vlib/v/gen/wasm/tests/builtin.vv

@@ -1,7 +1,6 @@
 fn test() {
 	print('hello!')
 	println('hello!')
-	panic('nooo!')
 }
 
 fn str_methods() {
@@ -16,3 +15,19 @@ fn str_implicit() {
 	a := 100
 	println(a + 10)
 }
+
+fn assertions() {
+	assert true, 'hello'
+	assert true
+
+	// assert false, 'no can do'
+}
+
+fn main() {
+	test()
+	str_methods()
+	str_implicit()
+	assertions()
+
+	// panic('nooo!')
+}

vlib/v/gen/wasm/tests/builtin.vv.out

@@ -0,0 +1,6 @@
+hello!hello!
+128-192322
+false
+false
+true
+110

vlib/v/gen/wasm/tests/control_flow.vv

@@ -59,15 +59,17 @@ fn addcfor() int {
 	return val
 }
 
-fn labelcfor() {
+fn labelcfor() (int, int) {
+	mut idx := 0
 	mut val := 0
 
 	hello: for {
 		for {
+			val++
 			if val == 10 {
 				continue hello
 			}
-			val++
+			idx++
 
 			if val == 100 {
 				break hello
@@ -75,6 +77,8 @@ fn labelcfor() {
 		}
 		break
 	}
+
+	return val, idx
 }
 
 fn infcfor() int {
@@ -89,3 +93,32 @@ fn infcfor() int {
 
 	return 0
 }
+
+fn main() {
+	println('--- func()')
+	println(func(10, true))
+	println(func(0, false))
+	println(func(0, true))
+
+	println('--- test()')
+	println(test(true))
+	println(test(false))
+	println(test(true && false))
+
+	println('--- boolfor()')
+	println(boolfor())
+
+	println('--- inffor()')
+	println(inffor())
+
+	println('--- addcfor()')
+	println(addcfor())
+
+	println('--- labelcfor()')
+	a, b := labelcfor()
+	println(a)
+	println(b)
+
+	println('--- infcfor()')
+	println(infcfor())
+}

vlib/v/gen/wasm/tests/control_flow.vv.out

@@ -0,0 +1,19 @@
+--- func()
+10
+0
+0
+--- test()
+2
+5
+5
+--- boolfor()
+1
+--- inffor()
+1
+--- addcfor()
+45
+--- labelcfor()
+100
+99
+--- infcfor()
+10

vlib/v/gen/wasm/tests/misc.vv

@@ -6,9 +6,10 @@ enum Hello as u64 {
 	e
 }
 
-fn enums() {
+fn enums() Hello {
 	mut a := Hello.a
 	a = .c
+	return a
 }
 
 struct AA {
@@ -19,6 +20,7 @@ struct AA {
 fn of() {
 	a := __offsetof(AA, b)
 	b := sizeof(AA)
+	_, _ := a, b
 }
 
 fn constant() int {
@@ -55,3 +57,35 @@ fn ptr_arith() {
 	}
 	println((*b).str())
 }
+
+fn defer_if(cond bool) {
+	if cond {
+		defer {
+			println('defer_if: defer!')
+		}
+	}
+	println('defer_if: start')
+}
+
+fn run_defer() {
+	defer {
+		println('defer!')
+	}
+	println('before defer')
+	defer_if(true)
+	defer_if(false)
+}
+
+fn main() {
+	println('ptr_arith')
+	ptr_arith()
+	run_defer()
+	println('constants')
+	println(runtime_init)
+	println(hello)
+	// println(float)
+	println(integer)
+	println('enums')
+	println(int(enums()))
+	println(sizeof(Hello))
+}

vlib/v/gen/wasm/tests/misc.vv.out

@@ -0,0 +1,17 @@
+ptr_arith
+12
+14
+102
+before defer
+defer_if: start
+defer_if: defer!
+defer_if: start
+defer!
+constants
+100
+hello
+
+888
+enums
+30
+8

vlib/v/gen/wasm/tests/multi_expr.vv

@@ -3,7 +3,7 @@ fn multi(a i16) i64 {
 	return one + two
 }
 
-pub fn multireturn(a int) (int, f64, i64) {
+pub fn multireturn(a int) (int, i64, i64) {
 	return 2, a + 2, 10 - a
 }
 
@@ -21,10 +21,94 @@ pub fn side_effect() int {
 	return 22
 }
 
-pub fn test_side_effect() int {
+pub fn run_side_effect() int {
 	mut a := 15
 
 	_, a = side_effect(), 10
 
 	return a
 }
+
+fn run_normal_stuff() {
+	println(multi(2))
+	{
+		a, b, c := multireturn(20)
+		println(a)
+		println(b)
+		println(c)
+	}
+	println(accept())
+	println(run_side_effect())
+}
+
+fn if_cond(cond bool) (int, int) {
+	return if cond { 10, 15 } else { 30, 35 }
+}
+
+struct AA {
+	a int
+	b int
+}
+
+fn take_struct(test AA) int {
+	return test.a
+}
+
+fn give_two_struct(cond bool) (AA, AA) {
+	return if cond {
+		AA{
+			a: 15
+		}, AA{
+			a: 15
+		}
+	} else {
+		AA{
+			a: 20
+		}, AA{
+			a: 592
+		}
+	}
+}
+
+fn give_struct() int {
+	return take_struct(AA{ a: 15 })
+}
+
+fn if_struct_test(cond bool) AA {
+	a := if cond {
+		AA{}
+	} else {
+		AA{
+			a: 125
+		}
+	}
+	return a
+}
+
+fn run_stmt_exprs() {
+	mut a := 0
+	mut b := 0
+	a, b = if_cond(true)
+	println(true)
+	println(a)
+	println(b)
+	a, b = if_cond(false)
+	println(false)
+	println(a)
+	println(b)
+	println(give_struct())
+	mut struc := if_struct_test(false)
+	println(struc.a)
+	struc = if_struct_test(true)
+	println(struc.a)
+	c, d := give_two_struct(false)
+	println(c.a)
+	println(d.a)
+}
+
+fn main() {
+	println('--- normal multi exprs')
+	run_normal_stuff()
+	println('--- struct based multi exprs/stmt exprs')
+	run_stmt_exprs()
+}

vlib/v/gen/wasm/tests/multi_expr.vv.out

@@ -0,0 +1,19 @@
+--- normal multi exprs
+12
+2
+22
+-10
+45
+10
+--- struct based multi exprs/stmt exprs
+true
+10
+15
+false
+30
+35
+15
+125
+0
+20
+592

vlib/v/gen/wasm/tests/structs.vv

@@ -142,7 +142,7 @@ struct Hello {
 }
 
 pub fn recurse() {
-	a := Hello{}
+	_ := Hello{}
 }
 
 struct DD {
@@ -177,3 +177,25 @@ fn postfix_test() {
 fn postfix_test_mut(mut a TEST) {
 	a.b++
 }
+
+fn main() {
+	zeroed()
+	field()
+	println(selector(0))
+	println(reassign(10))
+	println(give(42))
+	println(return_make(123))
+	accept()
+	println(accept_multi(5))
+	x, y := test(2, 3)
+	println(x)
+	println(y)
+	recurse()
+	z, w := valer()
+	println(z)
+	println(w)
+	postfix_test()
+	mut a := TEST{}
+	postfix_test_mut(mut a)
+	println(a.b)
+}

vlib/v/gen/wasm/tests/structs.vv.out

@@ -0,0 +1,10 @@
+32
+20
+42
+123
+10
+12
+8
+20
+30
+1

vlib/v/gen/wasm/tests/wasm_test.v

@@ -6,6 +6,23 @@ const is_verbose = os.getenv('VTEST_SHOW_CMD') != ''
 
 // TODO some logic copy pasted from valgrind_test.v and compiler_test.v, move to a module
 fn test_wasm() {
+	mut runtimes := ['wasmer', 'wasmtime', 'wavm', 'wasm3']
+	mut runtime_found := false
+
+	for runtime in runtimes {
+		basename := $if windows { runtime + '.exe' } $else { runtime }
+
+		if rf := os.find_abs_path_of_executable(basename) {
+			runtime_found = true
+			break
+		}
+	}
+
+	if !runtime_found {
+		eprintln('cannot find suitable wasm runtime, exiting...')
+		exit(0)
+	}
+
 	mut bench := benchmark.new_benchmark()
 	vexe := os.getenv('VEXE')
 	vroot := os.dir(vexe)
@@ -33,7 +50,7 @@ fn test_wasm() {
 		tmperrfile := '${dir}/${test}.tmperr'
 		outfile := '${dir}/${test}.out'
 		// force binaryen to print without colour
-		cmd := '${os.quoted_path(vexe)} -o - -b wasm ${os.quoted_path(full_test_path)} 2> ${os.quoted_path(tmperrfile)}'
+		cmd := '${os.quoted_path(vexe)} -b wasm run ${os.quoted_path(full_test_path)} 2> ${os.quoted_path(tmperrfile)}'
 		if is_verbose {
 			println(cmd)
 		}
@@ -65,6 +82,9 @@ fn test_wasm() {
 				bench.fail()
 				continue
 			}
+		} else {
+			os.write_file(outfile, res_wasm.output.trim_right('\r\n').replace('\r\n',
+				'\n'))!
 		}
 		bench.ok()
 		eprintln(bench.step_message_ok(relative_test_path))

vlib/v/help/build/build-wasm.txt

@@ -0,0 +1,25 @@
+This command compiles the given target, along with their dependencies,
+into an executable using the WebAssembly code generation backend.
+
+Usage:
+  v -b wasm [-options] ['run'] <target.v|target_directory> [run options]
+
+
+For more general build help, see also `v help build`.
+
+# Interfacing WebAssembly code generation, passing options to it:
+   -wasm-validate
+      After compiling the WebAssembly module, execute wasm-validate to validate the module.
+      Useful for debugging the compiler.
+
+   -os <browser|wasi>, -target-os <browser|wasi>
+      Change the target WebAssembly execution environment that V compiles for.
+
+      The `wasi` target is the default execution enviroment.
+        When targeting WASI, the generated WebAssembly module can be run in a variety of environments that support the WASI specification.
+        WASI provides a standardized interface to interact with the host operating system, allowing WebAssembly modules to perform tasks like file I/O, networking, and more.
+        The specific version of the WASI specification targeted by V is 'wasi_snapshot_preview1'.
+      
+      The `browser` target is an experimental environment that compiles for a stripped down builtin, for use in browsers.
+        The produced WebAssembly module will have functions exported that are `pub` and inside the `module main`.
+        See `examples/wasm/mandelbrot` for an example.

vlib/v/help/build/build.txt

@@ -45,6 +45,7 @@ NB: the build flags are shared with the run command too:
     * `js_node`           - V outputs JS source code to run with nodejs.
     * `js_freestanding`   - V outputs JS source code with no hard runtime dependency.
     * `native`            - V outputs a native executable directly (see -arch x64|arm64 and -os linux|macos) (EXPERIMENTAL).
+    * `wasm`              - V outputs a WebAssembly module directly (see -os wasi|browser) (EXPERIMENTAL).
 
   -d <flag>[=<value>], -define <flag>[=<value>]
     Define the provided flag.
@@ -209,6 +210,7 @@ NB: the build flags are shared with the run command too:
 For C-specific build flags, use `v help build-c`.
 For JS-specific build flags, use `v help build-js`.
 For Native-specific build flags, use `v help build-native`.
+For WebAssembly-specific build flags, use `v help build-wasm`.
 
 See also:
    `v help run` for documentation regarding `v run`.

vlib/v/pref/pref.v

@@ -228,6 +228,7 @@ pub mut:
 	// checker settings:
 	checker_match_exhaustive_cutoff_limit int = 12
 	thread_stack_size                     int = 8388608 // Change with `-thread-stack-size 4194304`. Note: on macos it was 524288, which is too small for more complex programs with many nested callexprs.
+	wasm_validate                         bool // validate webassembly code, by calling `wasm-validate`
 }
 
 pub fn parse_args(known_external_commands []string, args []string) (&Preferences, string) {
@@ -303,6 +304,9 @@ pub fn parse_args_and_show_errors(known_external_commands []string, args []strin
 		arg := args[i]
 		current_args := args[i..].clone()
 		match arg {
+			'-wasm-validate' {
+				res.wasm_validate = true
+			}
 			'-apk' {
 				res.is_apk = true
 				res.build_options << arg

vlib/v/transformer/transformer.v

@@ -666,6 +666,21 @@ pub fn (mut t Transformer) expr(mut node ast.Expr) ast.Expr {
 		ast.UnsafeExpr {
 			node.expr = t.expr(mut node.expr)
 		}
+		// segfaults with vlib/v/tests/const_fixed_array_containing_references_to_itself_test.v
+		/*
+		ast.Ident {
+			mut obj := node.obj
+			if obj !in [ast.Var, ast.ConstField, ast.GlobalField, ast.AsmRegister] {
+				obj = node.scope.find(node.name) or { return node }
+			}
+
+			match mut obj {
+				ast.ConstField {
+					obj.expr = t.expr(mut obj.expr)
+				}
+				else {}
+			}
+		}*/
 		else {}
 	}
 	return node

vlib/v/util/util.v

@@ -163,7 +163,7 @@ pub fn launch_tool(is_verbose bool, tool_name string, args []string) {
 		for emodule in emodules {
 			check_module_is_installed(emodule, is_verbose) or { panic(err) }
 		}
-		mut compilation_command := '${os.quoted_path(vexe)} -skip-unused '
+		mut compilation_command := '${os.quoted_path(vexe)} '
 		if tool_name in ['vself', 'vup', 'vdoctor', 'vsymlink'] {
 			// These tools will be called by users in cases where there
 			// is high chance of there being a problem somewhere. Thus

vlib/wasm/encoding.v

@@ -110,26 +110,22 @@ fn (mut mod Module) patch(ft Function) {
 	mod.buf << ft.code[ptr..]
 }
 
-// name
+fn (mut mod Module) name(name string) {
-pub fn (mut mod Module) name(name string) {
 	mod.u32(u32(name.len))
 	mod.buf << name.bytes()
 }
 
-// start_subsection
+fn (mut mod Module) start_subsection(sec Subsection) int {
-pub fn (mut mod Module) start_subsection(sec Subsection) int {
 	mod.buf << u8(sec)
 	return mod.patch_start()
 }
 
-// start_section
+fn (mut mod Module) start_section(sec Section) int {
-pub fn (mut mod Module) start_section(sec Section) int {
 	mod.buf << u8(sec)
 	return mod.patch_start()
 }
 
-// end_section
+fn (mut mod Module) end_section(tpatch int) {
-pub 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.name(ft.mod)
-				mod.buf << ft.mod.bytes()
+				mod.name(ft.name)
-				mod.u32(u32(ft.name.len))
-				mod.buf << ft.name.bytes()
 				mod.buf << 0x00 // function
 				mod.u32(u32(ft.tidx))
 			}
 			for gt in mod.global_imports {
-				mod.u32(u32(gt.mod.len))
+				mod.name(gt.mod)
-				mod.buf << gt.mod.bytes()
+				mod.name(gt.name)
-				mod.u32(u32(gt.name.len))
-				mod.buf << gt.name.bytes()
 				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`.