wasm2c: Fix test harness UB with SIMD

test/harness/wasm2c/simd_formatting.txt

@@ -0,0 +1,15 @@
+;;; TOOL: run-spec-wasm2c
+;;; ERROR: 1
+(module
+  (func (export "x") (param $x v128) (result v128) (local.get $x))
+)
+(assert_return (invoke "x" (v128.const i8x16 0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09 0x0A 0x0B 0x0C 0x0D 0x0E 0x0F))
+                           (v128.const i8x16 0xFF 0xFE 0xFD 0xFC 0xFB 0xFA 0xF9 0xF8 0xF7 0xF6 0xF5 0xF4 0xF3 0xF2 0xF1 0xF0))
+(;; STDERR ;;;
+Error running "out/test/harness/wasm2c/simd_formatting/simd_formatting" (1):
+None
+out/test/harness/wasm2c/simd_formatting/simd_formatting-main.c:384: assertion failed: in w2c_simd__formatting__0__wasm_x(&simd__formatting__0__wasm_instance, simde_wasm_i8x16_make(0u,1u,2u,3u,4u,5u,6u,7u,8u,9u,10u,11u,12u,13u,14u,15u)): expected <255 254 253 252 251 250 249 248 247 246 245 244 243 242 241 240 >, got <0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 >.
+;;; STDERR ;;)
+(;; STDOUT ;;;
+0/1 tests passed.
+;;; STDOUT ;;)

test/run-spec-wasm2c.py

@@ -408,7 +408,7 @@ def _SIMDConstantList(self, const):
         return ', '.join(self._Constant({'type': const['lane_type'], 'value': val}) for val in const['value'])
 
     def _SIMDFound(self, num, lane_type, lane_count):
-        return 'simde_wasm_%sx%d_extract_lane(actual, %d)' % (lane_type, lane_count, num)
+        return 'v128_%sx%d_extract_lane(actual, %d)' % (lane_type, lane_count, num)
 
     def _SIMDFoundList(self, lane_type, lane_count):
         return ', '.join(self._SIMDFound(num, lane_type, lane_count) for num in range(lane_count))
@@ -644,7 +644,10 @@ def main(args):
 
             # Run the resulting binary
             if options.run:
-                utils.Executable(main_exe, forward_stdout=True).RunWithArgs()
+                error = utils.Executable(main_exe, forward_stdout=True).RunWithArgsAndError()
+                if error:
+                    print(error, file=sys.stderr)
+                    return 1
 
     return 0
 

test/spec-wasm2c-prefix.c

@@ -13,6 +13,18 @@
 #include "wasm-rt-impl.h"
 #include "wasm-rt-exceptions.h"
 
+// like is_equal_TYPE below, always use unsigned for these
+#define v128_i8x16_extract_lane simde_wasm_u8x16_extract_lane
+#define v128_u8x16_extract_lane simde_wasm_u8x16_extract_lane
+#define v128_i16x8_extract_lane simde_wasm_u16x8_extract_lane
+#define v128_u16x8_extract_lane simde_wasm_u16x8_extract_lane
+#define v128_i32x4_extract_lane simde_wasm_u32x4_extract_lane
+#define v128_u32x4_extract_lane simde_wasm_u32x4_extract_lane
+#define v128_i64x2_extract_lane simde_wasm_u64x2_extract_lane
+#define v128_u64x2_extract_lane simde_wasm_u64x2_extract_lane
+#define v128_f32x4_extract_lane simde_wasm_f32x4_extract_lane
+#define v128_f64x2_extract_lane simde_wasm_f64x2_extract_lane
+
 static int g_tests_run;
 static int g_tests_passed;
 
@@ -143,8 +155,8 @@ static void error(const char* file, int line, const char* format, ...) {
 
 #define MULTI_T_UNPACK_(...) __VA_ARGS__
 #define MULTI_T_UNPACK(arg) MULTI_T_UNPACK_ arg
-#define MULTI_i8 "%su "
-#define MULTI_i16 "%su "
+#define MULTI_i8 "%" PRIu8 " "
+#define MULTI_i16 "%" PRIu16 " "
 #define MULTI_i32 "%u "
 #define MULTI_i64 "%" PRIu64 " "
 #define MULTI_f32 "%.9g "

test/utils.py

@@ -94,6 +94,13 @@ def RunWithArgs(self, *args, **kwargs):
         if error:
             raise error
 
+    def RunWithArgsAndError(self, *args, **kwargs):
+        stdout, stderr, error = self._RunWithArgsInternal(*args, **kwargs)
+        if stdout:
+            sys.stdout.write(stdout)
+        if error:
+            return error
+
     def AppendArg(self, arg):
         self.after_args.append(arg)