v.gen.js: simplify comptime if; catch up with cgen (fix #25295) (#25313)

vlib/builtin/js/int.js.v

@@ -17,8 +17,16 @@ pub const max_i32 = i32(2147483647)
 pub const min_i64 = i64(-9223372036854775807 - 1)
 pub const max_i64 = i64(9223372036854775807)
 
-pub const min_int = int(min_i32)
+pub const min_int = $if new_int ? && (arm64 || amd64 || rv64 || s390x || ppc64le || loongarch64) {
-pub const max_int = int(max_i32)
+	int(min_i64)
+} $else {
+	int(min_i32)
+}
+pub const max_int = $if new_int ? && (arm64 || amd64 || rv64 || s390x || ppc64le || loongarch64) {
+	int(max_i64)
+} $else {
+	int(max_i32)
+}
 
 pub const min_u8 = u8(0)
 pub const max_u8 = u8(255)

vlib/v/gen/js/comptime.v

@@ -18,334 +18,15 @@ fn (mut g JsGen) gen_branch_context_string() string {
 	return arr.join(',')
 }
 
-fn (mut g JsGen) comptime_if(node ast.IfExpr) {
+fn (mut g JsGen) comptime_if_result(branch ast.IfBranch) bool {
-	if !node.is_expr && !node.has_else && node.branches.len == 1 {
+	idx_str := g.gen_branch_context_string() + '|id=${branch.id}|'
-		if node.branches[0].stmts.len == 0 {
+	$if debug_comptime_branch_context ? {
-			// empty ifdef; result of target OS != conditional => skip
+		g.write('/* ${idx_str} */')
-			return
-		}
 	}
-
+	if comptime_is_true := g.table.comptime_is_true[idx_str] {
-	mut comptime_branch_context_str := g.gen_branch_context_string()
+		return comptime_is_true.val
-	mut is_true := ast.ComptTimeCondResult{}
+	} else {
-	for i, branch in node.branches {
+		panic('checker error: cond result idx string not found => [${idx_str}]')
-		idx_str := comptime_branch_context_str + '|id=${branch.id}|'
+		return false
-		if comptime_is_true := g.table.comptime_is_true[idx_str] {
-			is_true = comptime_is_true
-		} else {
-			panic('checker error: cond result idx string not found => [${idx_str}]')
-			return
-		}
-		if i == node.branches.len - 1 && node.has_else {
-			g.writeln('else')
-		} else {
-			result := if is_true.val { '1' } else { '0' }
-			if i == 0 {
-				g.writeln('if (${result})')
-			} else {
-				g.writeln('else if (${result})')
-			}
-			$if debug_comptime_branch_context ? {
-				g.writeln('// ${node.branches[i].cond} generic=[${comptime_branch_context_str}]')
-			}
-		}
-
-		if node.is_expr {
-			print('${branch.stmts}')
-			len := branch.stmts.len
-			if len > 0 {
-				last := branch.stmts.last() as ast.ExprStmt
-				if len > 1 {
-					tmp := g.new_tmp_var()
-					g.inc_indent()
-					g.writeln('let ${tmp};')
-					g.writeln('{')
-					g.stmts(branch.stmts[..len - 1])
-					g.write('\t${tmp} = ')
-					g.stmt(last)
-					g.writeln('}')
-					g.dec_indent()
-					g.writeln('${tmp};')
-				} else {
-					g.stmt(last)
-				}
-			}
-		} else {
-			g.writeln('{')
-			if is_true.val {
-				g.stmts(branch.stmts)
-			}
-			g.writeln('}')
-		}
 	}
 }
-
-/*
-// returning `false` means the statements inside the $if can be skipped
-*/
-// returns the value of the bool comptime expression
-fn (mut g JsGen) comptime_if_cond(cond ast.Expr, pkg_exist bool) bool {
-	match cond {
-		ast.BoolLiteral {
-			g.expr(cond)
-			return true
-		}
-		ast.ParExpr {
-			g.write('(')
-			is_cond_true := g.comptime_if_cond(cond.expr, pkg_exist)
-			g.write(')')
-			return is_cond_true
-		}
-		ast.PrefixExpr {
-			g.write(cond.op.str())
-			return g.comptime_if_cond(cond.right, pkg_exist)
-		}
-		ast.PostfixExpr {
-			ifdef := g.comptime_if_to_ifdef((cond.expr as ast.Ident).name, true) or {
-				verror(err.msg())
-				return false
-			}
-			g.write('${ifdef}')
-			return true
-		}
-		ast.InfixExpr {
-			match cond.op {
-				.and, .logical_or {
-					l := g.comptime_if_cond(cond.left, pkg_exist)
-					g.write(' ${cond.op} ')
-					r := g.comptime_if_cond(cond.right, pkg_exist)
-					return if cond.op == .and { l && r } else { l || r }
-				}
-				.key_is, .not_is {
-					left := cond.left
-					mut name := ''
-					mut exp_type := ast.no_type
-					got_type := (cond.right as ast.TypeNode).typ
-					// Handle `$if x is Interface {`
-					// mut matches_interface := 'false'
-					if left is ast.TypeNode && cond.right is ast.TypeNode
-						&& g.table.sym(got_type).kind == .interface {
-						// `$if Foo is Interface {`
-						interface_sym := g.table.sym(got_type)
-						if interface_sym.info is ast.Interface {
-							// q := g.table.sym(interface_sym.info.types[0])
-							checked_type := g.unwrap_generic(left.typ)
-							// TODO: PERF this check is run twice (also in the checker)
-							// store the result in a field
-							is_true := g.table.does_type_implement_interface(checked_type,
-								got_type)
-							// true // exp_type in interface_sym.info.types
-							if cond.op == .key_is {
-								if is_true {
-									g.write('1')
-								} else {
-									g.write('0')
-								}
-								return is_true
-							} else if cond.op == .not_is {
-								if is_true {
-									g.write('0')
-								} else {
-									g.write('1')
-								}
-								return !is_true
-							}
-							// matches_interface = '/*iface:$got_type $exp_type*/ true'
-							//}
-						}
-					} else if left is ast.SelectorExpr {
-						name = '${left.expr}.${left.field_name}'
-						exp_type = g.comptime_var_type_map[name]
-					} else if left is ast.TypeNode {
-						// this is only allowed for generics currently, otherwise blocked by checker
-						exp_type = g.unwrap_generic(left.typ)
-					}
-
-					if cond.op == .key_is {
-						g.write('${exp_type} == ${got_type}')
-						return exp_type == got_type
-					} else {
-						g.write('${exp_type} != ${got_type}')
-						return exp_type != got_type
-					}
-				}
-				.eq, .ne {
-					// TODO: Implement `$if method.args.len == 1`
-					g.write('1')
-					return true
-				}
-				else {
-					return true
-				}
-			}
-		}
-		ast.Ident {
-			ifdef := g.comptime_if_to_ifdef(cond.name, false) or { 'true' } // handled in checker
-			g.write('${ifdef}')
-			return true
-		}
-		ast.ComptimeCall {
-			g.write('${pkg_exist}')
-			return true
-		}
-		else {
-			// should be unreachable, but just in case
-			g.write('1')
-			return true
-		}
-	}
-}
-
-fn (mut g JsGen) comptime_if_to_ifdef(name string, is_comptime_option bool) !string {
-	match name {
-		// platforms/os-es:
-		'windows' {
-			return '(\$process.platform == "windows")'
-		}
-		'ios' {
-			return '(\$process.platform == "darwin")'
-		}
-		'macos' {
-			return '(\$process.platform == "darwin")'
-		}
-		'mach' {
-			return '(\$process.platform == "darwin")'
-		}
-		'darwin' {
-			return '(\$process.platform == "darwin")'
-		}
-		'linux' {
-			return '(\$process.platform == "linux")'
-		}
-		'freebsd' {
-			return '(\$process.platform == "freebsd")'
-		}
-		'openbsd' {
-			return '(\$process.platform == "openbsd")'
-		}
-		'bsd' {
-			return '(\$process.platform == "freebsd" || (\$process.platform == "openbsd"))'
-		}
-		'android' {
-			return '(\$process.platform == "android")'
-		}
-		'solaris' {
-			return '(\$process.platform == "sunos")'
-		}
-		'js_node' {
-			if g.pref.backend == .js_node {
-				return 'true'
-			} else {
-				return 'false'
-			}
-		}
-		'js_freestanding' {
-			if g.pref.backend == .js_freestanding {
-				return 'true'
-			} else {
-				return 'false'
-			}
-		}
-		'js_browser' {
-			if g.pref.backend == .js_browser {
-				return 'true'
-			} else {
-				return 'false'
-			}
-		}
-		'es5' {
-			if g.pref.output_es5 {
-				return 'true'
-			} else {
-				return 'false'
-			}
-		}
-		//
-		'js' {
-			return 'true'
-		}
-		'native' {
-			return 'false'
-		}
-		// compilers:
-		'gcc' {
-			return 'false'
-		}
-		'tinyc' {
-			return 'false'
-		}
-		'clang' {
-			return 'false'
-		}
-		'mingw' {
-			return 'false'
-		}
-		'msvc' {
-			return 'false'
-		}
-		'cplusplus' {
-			return 'false'
-		}
-		// other:
-		'threads' {
-			return 'false'
-		}
-		'gcboehm' {
-			return 'false'
-		}
-		// todo(playX): these should return true or false depending on CLI options
-		'debug' {
-			return 'false'
-		}
-		'prod' {
-			return 'false'
-		}
-		'test' {
-			return 'false'
-		}
-		'glibc' {
-			return 'false'
-		}
-		'prealloc' {
-			return 'false'
-		}
-		'no_bounds_checking' {
-			return 'checkDefine("CUSTOM_DEFINE_no_bounds_checking")'
-		}
-		'freestanding' {
-			return '_VFREESTANDING'
-		}
-		'autofree' {
-			return '_VAUTOFREE'
-		}
-		// architectures:
-		'amd64' {
-			return '(\$process.arch == "x64")'
-		}
-		'aarch64', 'arm64' {
-			return '(\$process.arch == "arm64)'
-		}
-		// bitness:
-		'x64' {
-			return '(\$process.arch == "x64")'
-		}
-		'x32' {
-			return '(\$process.arch == "x32")'
-		}
-		// endianness:
-		'little_endian' {
-			return '(\$os.endianness == "LE")'
-		}
-		'big_endian' {
-			return '(\$os.endianness == "BE")'
-		}
-		else {
-			if is_comptime_option
-				|| (g.pref.compile_defines_all.len > 0 && name in g.pref.compile_defines_all) {
-				return 'checkDefine("CUSTOM_DEFINE_${name}")'
-			}
-			return error('bad os ifdef name "${name}"') // should never happen, caught in the checker
-		}
-	}
-	return error('none')
-}

vlib/v/gen/js/js.v

@@ -2722,10 +2722,6 @@ fn (mut g JsGen) need_tmp_var_in_if(node ast.IfExpr) bool {
 }
 
 fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
-	if node.is_comptime {
-		g.comptime_if(node)
-		return
-	}
 	// For simpe if expressions we can use C's `?:`
 	// `if x > 0 { 1 } else { 2 }` => `(x > 0)? (1) : (2)`
 	// For if expressions with multiple statements or another if expression inside, it's much
@@ -2734,6 +2730,8 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 	// Always use this in -autofree, since ?: can have tmp expressions that have to be freed.
 	needs_tmp_var := g.need_tmp_var_in_if(node)
 	tmp := if needs_tmp_var { g.new_tmp_var() } else { '' }
+	mut is_true := false
+	mut comptime_has_true_branch := false
 
 	if needs_tmp_var {
 		if node.typ.has_flag(.option) {
@@ -2746,14 +2744,32 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 		prev := g.inside_ternary
 		g.inside_ternary = true
 		for i, branch in node.branches {
-			if i > 0 {
+			if node.is_comptime {
-				g.write(' : ')
+				$if debug_comptime_branch_context ? {
-			}
+					g.write('/* ${branch.cond} */')
-			if i < node.branches.len - 1 || !node.has_else {
+				}
-				g.write('(')
+				// comptime $if, only generate the true branch
-				g.expr(branch.cond)
+				if i < node.branches.len - 1 || !node.has_else {
-				g.write(').valueOf()')
+					if !g.comptime_if_result(branch) {
-				g.write(' ? ')
+						continue
+					}
+					comptime_has_true_branch = true
+				} else {
+					// else branch
+					if comptime_has_true_branch {
+						continue
+					}
+				}
+			} else {
+				if i > 0 {
+					g.write(' : ')
+				}
+				if i < node.branches.len - 1 || !node.has_else {
+					g.write('(')
+					g.expr(branch.cond)
+					g.write(').valueOf()')
+					g.write(' ? ')
+				}
 			}
 			g.stmts(branch.stmts)
 		}
@@ -2784,6 +2800,8 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 		}
 	}
 
+	is_true = false
+	comptime_has_true_branch = false
 	for i, branch in node.branches {
 		if i > 0 {
 			g.write('} else ')
@@ -2796,6 +2814,9 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 				cvar_name := guard_vars[guard_idx]
 				g.writeln('\tlet err = ${cvar_name}.err;')
 			}
+			if node.is_comptime && !comptime_has_true_branch {
+				is_true = true
+			}
 		} else {
 			match branch.cond {
 				ast.IfGuardExpr {
@@ -2809,7 +2830,20 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 						g.writeln('if (${var_name}.state == 0) {')
 					} else {
 						g.write('if (${var_name} = ')
-						g.expr(branch.cond.expr)
+						if node.is_comptime {
+							$if debug_comptime_branch_context ? {
+								g.write('/* ${branch.cond} */')
+							}
+							is_true = g.comptime_if_result(branch)
+							if is_true {
+								g.write('1')
+								comptime_has_true_branch = true
+							} else {
+								g.write('0')
+							}
+						} else {
+							g.expr(branch.cond.expr)
+						}
 						g.writeln(', ${var_name}.state == 0) {')
 					}
 					if short_opt || branch.cond.vars[0].name != '_' {
@@ -2820,7 +2854,17 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 								branch.cond.vars[0].name
 							}
 							g.write('\tlet ${cond_var_name} = ')
-							g.expr(branch.cond.expr)
+							if node.is_comptime {
+								is_true = g.comptime_if_result(branch)
+								if is_true {
+									g.write('1')
+									comptime_has_true_branch = true
+								} else {
+									g.write('0')
+								}
+							} else {
+								g.expr(branch.cond.expr)
+							}
 							g.writeln(';')
 						} else {
 							g.writeln('\tlet ${branch.cond.vars}[0].name = ${var_name}.data;')
@@ -2828,16 +2872,31 @@ fn (mut g JsGen) gen_if_expr(node ast.IfExpr) {
 					}
 				}
 				else {
-					g.write('if ((')
+					if node.is_comptime {
-					g.expr(branch.cond)
+						g.write('if (')
-					g.writeln(').valueOf()) {')
+						$if debug_comptime_branch_context ? {
+							g.write('/* ${branch.cond} */')
+						}
+						is_true = g.comptime_if_result(branch)
+						if is_true {
+							g.write('1')
+							comptime_has_true_branch = true
+						} else {
+							g.write('0')
+						}
+						g.writeln(') {')
+					} else {
+						g.write('if ((')
+						g.expr(branch.cond)
+						g.writeln(').valueOf()) {')
+					}
 				}
 			}
 		}
 		g.inc_indent()
 		if needs_tmp_var {
 			g.stmts_with_tmp_var(branch.stmts, tmp)
-		} else {
+		} else if (node.is_comptime && is_true) || !node.is_comptime {
 			g.stmts(branch.stmts)
 		}
 		g.dec_indent()