Fix a bug in the shr_s instruction implementation

kateinoigakukun · kateinoigakukun · commit 4f150c15e277 · 2024-09-29T22:50:37.000+09:00
diff --git a/FuzzTesting/FailCases/FuzzDifferential/diff-74668.wasm b/FuzzTesting/FailCases/FuzzDifferential/diff-74668.wasm
diff --git a/Sources/WasmKit/Execution/Value.swift b/Sources/WasmKit/Execution/Value.swift
@@ -130,8 +130,8 @@ extension RawUnsignedInteger {
         return self << shift
     }
     func shrS(_ other: Self) -> Self {
-        let shift = other.signed % Self.Signed(Self.bitWidth)
-        return (self.signed >> shift.unsigned).unsigned
+        let shift = other % Self(Self.bitWidth)
+        return (self.signed >> shift).unsigned
     }
     func shrU(_ other: Self) -> Self {
         let shift = other % Self(Self.bitWidth)
diff --git a/Tests/WasmKitTests/ExtraSuite/shr_s.wast b/Tests/WasmKitTests/ExtraSuite/shr_s.wast
@@ -0,0 +1,8 @@
+(module
+  (func (export "i64.shr_s") (param i64) (param i64) (result i64)
+    (i64.shr_s (local.get 0) (local.get 1))
+  )
+)
+
+(assert_return (invoke "i64.shr_s" (i64.const -1309934030728401938) (i64.const -1309934030728401938)) (i64.const -18616))
+

Original file line number	Diff line number	Diff line change
`@@ -130,8 +130,8 @@ extension RawUnsignedInteger {`
`130`	`130`	`return self << shift`
`131`	`131`	`}`
`132`	`132`	`func shrS(_ other: Self) -> Self {`
`133`		`- let shift = other.signed % Self.Signed(Self.bitWidth)`
`134`		`- return (self.signed >> shift.unsigned).unsigned`
	`133`	`+ let shift = other % Self(Self.bitWidth)`
	`134`	`+ return (self.signed >> shift).unsigned`
`135`	`135`	`}`
`136`	`136`	`func shrU(_ other: Self) -> Self {`
`137`	`137`	`let shift = other % Self(Self.bitWidth)`