wast2json: Support outputting negative numbers for v128 values

WebAssembly · Jun 10, 2024 · 29241a8 · 29241a8
1 parent 4beb525
commit 29241a8
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Showing 3 changed files with 49 additions and 7 deletions.
diff --git a/include/wabt/ir.h b/include/wabt/ir.h
@@ -156,6 +156,16 @@ struct Const {
  void set_externref(uintptr_t x) { From(Type::ExternRef, x); }
  void set_null(Type type) { From<uintptr_t>(type, kRefNullBits); }
 
+ bool is_negative(int lane = 0) const {
+ return lane < 16 && is_negative_[lane];
+ }
+
+ void set_is_negative(int lane, bool is_negative) {
+ if (lane < 16) {
+ is_negative_[lane] = is_negative;
+ }
+ }
+
  bool is_expected_nan(int lane = 0) const {
  return expected_nan(lane) != ExpectedNan::None;
  }
@@ -198,6 +208,9 @@ struct Const {
  Type type_;
  Type lane_type_; // Only valid if type_ == Type::V128.
  v128 data_;
+ // Used for wast2json, we need to know if a number is negative to prefix it
+ // properly.
+ bool is_negative_[16];
  ExpectedNan nan_[4];
 };
 using ConstVector = std::vector<Const>;

diff --git a/src/binary-writer-spec.cc b/src/binary-writer-spec.cc
@@ -216,14 +216,14 @@ void BinaryWriterSpec::WriteConst(const Const& const_) {
  WriteString("i32");
  WriteSeparator();
  WriteKey("value");
- json_stream_->Writef("\"%u\"", const_.u32());
+ json_stream_->Writef("\"%" PRIi32 "\"", const_.u32());
  break;
 
  case Type::I64:
  WriteString("i64");
  WriteSeparator();
  WriteKey("value");
- json_stream_->Writef("\"%" PRIu64 "\"", const_.u64());
+ json_stream_->Writef("\"%" PRIi64 "\"", const_.u64());
  break;
 
  case Type::F32:
@@ -266,22 +266,49 @@ void BinaryWriterSpec::WriteConst(const Const& const_) {
  json_stream_->Writef("[");
 
  for (int lane = 0; lane < const_.lane_count(); ++lane) {
+ auto negative_char = const_.is_negative(lane) ? "-" : "";
  switch (const_.lane_type()) {
  case Type::I8:
- json_stream_->Writef("\"%u\"", const_.v128_lane<uint8_t>(lane));
+ if (const_.is_negative(lane)) {
+ auto converted = UINT8_MAX - const_.v128_lane<uint8_t>(lane) + 1;
+ json_stream_->Writef("\"-%u\"", converted);
+
+ } else {
+ json_stream_->Writef("\"%s%u\"", negative_char,
+ const_.v128_lane<uint8_t>(lane));
+ }
  break;
 
  case Type::I16:
- json_stream_->Writef("\"%u\"", const_.v128_lane<uint16_t>(lane));
+ if (const_.is_negative(lane)) {
+ auto converted =
+ UINT16_MAX - const_.v128_lane<uint16_t>(lane) + 1;
+ json_stream_->Writef("\"-%u\"", converted);
+ } else {
+ json_stream_->Writef("\"%u\"", const_.v128_lane<uint16_t>(lane));
+ }
  break;
 
  case Type::I32:
- json_stream_->Writef("\"%u\"", const_.v128_lane<uint32_t>(lane));
+ if (const_.is_negative(lane)) {
+ auto converted =
+ UINT32_MAX - const_.v128_lane<uint32_t>(lane) + 1;
+ json_stream_->Writef("\"-%u\"", converted);
+ } else {
+ json_stream_->Writef("\"%s%u\"", negative_char,
+ const_.v128_lane<uint32_t>(lane));
+ }
  break;
 
  case Type::I64:
- json_stream_->Writef("\"%" PRIu64 "\"",
- const_.v128_lane<uint64_t>(lane));
+ if (const_.is_negative(lane)) {
+ auto converted =
+ UINT64_MAX - const_.v128_lane<uint64_t>(lane) + 1;
+ json_stream_->Writef("\"-%" PRIu64 "\"", converted);
+ } else {
+ json_stream_->Writef("\"%s%" PRIu64 "\"", negative_char,
+ const_.v128_lane<uint64_t>(lane));
+ }
  break;
 
  case Type::F32:

diff --git a/src/wast-parser.cc b/src/wast-parser.cc
@@ -2644,6 +2644,8 @@ Result WastParser::ParseSimdV128Const(Const* const_,
  if (integer) {
  std::string_view sv = Consume().literal().text;
 
+ const_->set_is_negative(lane, sv[0] == '-');
+
  switch (lane_count) {
  case 16: {
  uint8_t value = 0;