[wasm] Update {i32,i64}.const to use signed leb128

test/unittests/wasm/decoder-unittest.cc

Index: test/unittests/wasm/decoder-unittest.cc
diff --git a/test/unittests/wasm/decoder-unittest.cc b/test/unittests/wasm/decoder-unittest.cc
index d773c955c0454e629d7ac501d02971a9352edc53..11d68f161eecfa32adf4faa2050cb329e1fff671 100644
--- a/test/unittests/wasm/decoder-unittest.cc
+++ b/test/unittests/wasm/decoder-unittest.cc
@@ -428,6 +428,26 @@ TEST_F(DecoderTest, ReadU32v_extra_bits) {
   }
 }
 
+TEST_F(DecoderTest, ReadI32v_extra_bits_negative) {
+  // OK for negative signed values to have extra ones.
+  int length = 0;
+  byte data[] = {0xff, 0xff, 0xff, 0xff, 0x7f};
+  decoder.Reset(data, data + sizeof(data));
+  decoder.checked_read_i32v(decoder.start(), 0, &length);
+  EXPECT_EQ(5, length);
+  EXPECT_TRUE(decoder.ok());
+}
+
+TEST_F(DecoderTest, ReadI32v_extra_bits_positive) {
+  // Not OK for positive signed values to have extra ones.
+  int length = 0;
+  byte data[] = {0x80, 0x80, 0x80, 0x80, 0x77};
+  decoder.Reset(data, data + sizeof(data));
+  decoder.checked_read_i32v(decoder.start(), 0, &length);
+  EXPECT_EQ(5, length);
+  EXPECT_FALSE(decoder.ok());
+}
+
 TEST_F(DecoderTest, ReadU32v_Bits) {
   // A more exhaustive test.
   const int kMaxSize = 5;
@@ -587,8 +607,7 @@ TEST_F(DecoderTest, ReadI64v_Bits) {
 
       int length = 1 + i / 7;
       for (int j = 0; j < kMaxSize; j++) {
-        const uint64_t uval = bit_cast<uint64_t>(val);
-        data[j] = static_cast<byte>((uval >> (7 * j)) & MASK_7);
+        data[j] = static_cast<byte>((val >> (7 * j)) & MASK_7);
       }
       for (int j = 0; j < length - 1; j++) {
         data[j] |= 0x80;
@@ -623,6 +642,26 @@ TEST_F(DecoderTest, ReadU64v_extra_bits) {
   }
 }
 
+TEST_F(DecoderTest, ReadI64v_extra_bits_negative) {
+  // OK for negative signed values to have extra ones.
+  int length = 0;
+  byte data[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f};
+  decoder.Reset(data, data + sizeof(data));
+  decoder.checked_read_i64v(decoder.start(), 0, &length);
+  EXPECT_EQ(10, length);
+  EXPECT_TRUE(decoder.ok());
+}
+
+TEST_F(DecoderTest, ReadI64v_extra_bits_positive) {
+  // Not OK for positive signed values to have extra ones.
+  int length = 0;
+  byte data[] = {0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x77};
+  decoder.Reset(data, data + sizeof(data));
+  decoder.checked_read_i64v(decoder.start(), 0, &length);
+  EXPECT_EQ(10, length);
+  EXPECT_FALSE(decoder.ok());
+}
+
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8