WAT: Ban non-power-of-2 alignment values

kateinoigakukun · kateinoigakukun · commit f2e7033d21e1 · 2024-10-03T12:02:28.000+09:00
diff --git a/Sources/WAT/Parser/ExpressionParser.swift b/Sources/WAT/Parser/ExpressionParser.swift
@@ -398,6 +398,10 @@ struct ExpressionParser<Visitor: InstructionVisitor> {
             try parser.consume()
             var subParser = Parser(String(maybeAlign.dropFirst(alignPrefix.count)))
             align = try subParser.expectUnsignedInt(UInt32.self)
+
+            if align == 0 || align & (align - 1) != 0 {
+                throw WatParserError("alignment must be a power of 2", location: subParser.lexer.location())
+            }
         }
         return MemArg(offset: offset, align: align)
     }
diff --git a/Tests/WATTests/EncoderTests.swift b/Tests/WATTests/EncoderTests.swift
@@ -107,8 +107,6 @@ class EncoderTests: XCTestCase {
 
             var stats = CompatibilityTestStats()
             let excluded: [String] = [
-                "align.wast",
-                "align64.wast",
                 "block.wast",
                 "call_indirect.wast",
                 "const.wast",

Original file line number	Diff line number	Diff line change
`@@ -398,6 +398,10 @@ struct ExpressionParser<Visitor: InstructionVisitor> {`
`398`	`398`	`try parser.consume()`
`399`	`399`	`var subParser = Parser(String(maybeAlign.dropFirst(alignPrefix.count)))`
`400`	`400`	`align = try subParser.expectUnsignedInt(UInt32.self)`
	`401`	`+`
	`402`	`+ if align == 0 \|\| align & (align - 1) != 0 {`
	`403`	`+ throw WatParserError("alignment must be a power of 2", location: subParser.lexer.location())`
	`404`	`+ }`
`401`	`405`	`}`
`402`	`406`	`return MemArg(offset: offset, align: align)`
`403`	`407`	`}`