perfetto: support big-endian in trace_processor_shell paths

include/perfetto/base/endian.h

@@ -224,6 +224,9 @@ inline double HostToLE(double x) {
   return HostToLEDouble(x);
 }
 
+inline uint16_t LEToHost(uint16_t x) {
+  return LE16ToHost(x);
+}
 inline uint32_t LEToHost(uint32_t x) {
   return LE32ToHost(x);
 }

src/trace_processor/core/dataframe/arrow_deserializer.cc

@@ -520,6 +520,7 @@ base::StatusOr<Dataframe> DeserializeFromArrow(
     const util::TraceBlobViewReader& data,
     StringPool* pool,
     const DataframeSpec& spec) {
+#if PERFETTO_IS_LITTLE_ENDIAN()
   if (spec.column_names.size() != spec.column_specs.size() ||
       spec.column_names.size() > std::numeric_limits<uint32_t>::max()) {
     return base::ErrStatus("Invalid dataframe spec");
@@ -600,6 +601,10 @@ base::StatusOr<Dataframe> DeserializeFromArrow(
   ++dataframe.non_column_mutations_;
   dataframe.Finalize();
   return dataframe;
+#else // PERFETTO_IS_LITTLE_ENDIAN()
+  return base::ErrStatus(
+      "Arrow deserialization is not supported on big-endian hosts");
+#endif // PERFETTO_IS_LITTLE_ENDIAN()
 }
 
 }  // namespace perfetto::trace_processor::core::dataframe

src/trace_processor/core/dataframe/arrow_internal.h

@@ -29,8 +29,6 @@
 
 namespace perfetto::trace_processor::core::dataframe::arrow_internal {
 
-static_assert(PERFETTO_IS_LITTLE_ENDIAN());
-
 // Constants and packed structs below mirror the official Arrow flatbuffer
 // schema. Keeping them together makes the serializer and deserializer use the
 // same wire definitions without depending on the full Arrow library.

src/trace_processor/core/dataframe/arrow_serializer.cc

@@ -623,6 +623,7 @@ base::Status ArrowSerializer::BuildFileFraming(const BodyPlan& plan) {
 base::StatusOr<size_t> ArrowSerializer::Prepare(const Dataframe& dataframe,
                                                 const StringPool& pool) {
   Reset();
+#if PERFETTO_IS_LITTLE_ENDIAN()
   if (!dataframe.finalized()) {
     return base::ErrStatus(
         "Arrow serialization requires a finalized dataframe");
@@ -654,6 +655,10 @@ base::StatusOr<size_t> ArrowSerializer::Prepare(const Dataframe& dataframe,
   prepared_string_pool_ = &pool;
   prepared_mutations_ = dataframe.mutations();
   return static_cast<size_t>(total);
+#else // PERFETTO_IS_LITTLE_ENDIAN()
+  return base::ErrStatus(
+      "Arrow serialization is not supported on big-endian hosts");
+#endif // PERFETTO_IS_LITTLE_ENDIAN()
 }
 
 base::Status ArrowSerializer::WriteDictionary(const DictionaryPlan& dictionary,

src/trace_processor/core/util/bit_vector.h

@@ -87,16 +87,22 @@ struct BitVector {
   // ceil(size / 8) bytes holding bit i at byte i / 8, bit i % 8. This is the
   // layout of the words below, so the bitmap is taken verbatim.
   static BitVector CreateFromBitmap(const uint8_t* bitmap, uint64_t size) {
-    static_assert(PERFETTO_IS_LITTLE_ENDIAN());
     if (size == 0) {
       return {};
     }
     auto words = FlexVector<uint64_t>::CreateWithSize((size + 63u) / 64u);
     size_t bitmap_bytes = static_cast<size_t>((size + 7u) / 8u);
     size_t word_bytes = words.size() * sizeof(uint64_t);
+#if PERFETTO_IS_LITTLE_ENDIAN()
     memcpy(words.data(), bitmap, bitmap_bytes);
     memset(reinterpret_cast<uint8_t*>(words.data()) + bitmap_bytes, 0,
            word_bytes - bitmap_bytes);
+#else
+    memset(words.data(), 0, word_bytes);
+    for (size_t i = 0; i < bitmap_bytes; ++i) {
+      words[i / 8u] |= static_cast<uint64_t>(bitmap[i]) << (8u * (i % 8u));
+    }
+#endif
     // Bits past `size` are unspecified in the source bitmap.
     if (size % 64u != 0u) {
       words.back() &= (1ull << (size % 64u)) - 1ull;

src/trace_processor/importers/art_method/art_method_tokenizer.cc

@@ -27,6 +27,7 @@
 #include <utility>
 #include <vector>
 
+#include "perfetto/base/endian.h"
 #include "perfetto/base/logging.h"
 #include "perfetto/base/status.h"
 #include "perfetto/ext/base/status_macros.h"
@@ -80,20 +81,20 @@ std::string ConstructPathname(const std::string& class_name,
 
 uint64_t ToLong(const TraceBlobView& tbv) {
   uint64_t x = 0;
-  memcpy(base::AssumeLittleEndian(&x), tbv.data(), tbv.size());
-  return x;
+  memcpy(&x, tbv.data(), tbv.size());
+  return base::LEToHost(x);
 }
 
 uint32_t ToInt(const TraceBlobView& tbv) {
   uint32_t x = 0;
-  memcpy(base::AssumeLittleEndian(&x), tbv.data(), tbv.size());
-  return x;
+  memcpy(&x, tbv.data(), tbv.size());
+  return base::LEToHost(x);
 }
 
 uint16_t ToShort(const TraceBlobView& tbv) {
   uint16_t x = 0;
-  memcpy(base::AssumeLittleEndian(&x), tbv.data(), tbv.size());
-  return x;
+  memcpy(&x, tbv.data(), tbv.size());
+  return base::LEToHost(x);
 }
 
 }  // namespace

src/trace_processor/importers/art_method/art_method_v2_tokenizer.cc

@@ -25,6 +25,7 @@
 #include <string>
 #include <vector>
 
+#include "perfetto/base/endian.h"
 #include "perfetto/base/logging.h"
 #include "perfetto/base/status.h"
 #include "perfetto/ext/base/status_macros.h"
@@ -91,13 +92,10 @@ const uint8_t* DecodeSignedLeb128(const uint8_t* data,
 
 // Reads a simple little-endian integer from the byte stream.
 uint64_t ReadNumber(const uint8_t* ptr, size_t num_bytes) {
-  static_assert(PERFETTO_IS_LITTLE_ENDIAN(),
-                "ART Method traces are little-endian. Perfetto requires a "
-                "little-endian host to parse these effectively.");
   PERFETTO_DCHECK(num_bytes <= sizeof(uint64_t));
   uint64_t number = 0;
   memcpy(&number, ptr, num_bytes);
-  return number;
+  return base::LEToHost(number);
 }
 
 std::string ConstructPathname(base::StringView class_name,

src/trace_processor/plugins/wattson/table_function.cc

@@ -25,7 +25,7 @@
 #include <utility>
 #include <vector>
 
-#include "perfetto/base/compiler.h"
+#include "perfetto/base/endian.h"
 #include "perfetto/base/logging.h"
 #include "perfetto/base/status.h"
 #include "perfetto/ext/base/status_or.h"
@@ -46,21 +46,18 @@ using core::dataframe::ColumnSpec;
 using core::dataframe::Dataframe;
 using core::dataframe::DataframeSpec;
 
-static_assert(PERFETTO_IS_LITTLE_ENDIAN(),
-              "wattson curve blobs are little-endian and require a "
-              "little-endian host");
-
 class WattsonCurvesBlobReader {
  public:
   explicit WattsonCurvesBlobReader(const uint8_t* data, size_t size)
       : data_(data), size_(size) {}
 
+  // Curve blobs are little-endian.
   template <typename T>
   T Read() {
     static_assert(std::is_trivially_copyable_v<T>);
     T value;
     ReadInto(&value, sizeof(T));
-    return value;
+    return base::LEToHost(value);
   }
 
   base::StringView ReadStringView(uint16_t size) {

src/trace_processor/util/zip_reader.cc

@@ -27,6 +27,7 @@
 #include <vector>
 
 #include "perfetto/base/build_config.h"
+#include "perfetto/base/endian.h"
 #include "perfetto/base/logging.h"
 #include "perfetto/base/status.h"
 #include "perfetto/base/time.h"
@@ -86,9 +87,9 @@ const uint16_t kDeflate = 8;
 template <typename T>
 T ReadAndAdvance(const uint8_t** ptr) {
   T res{};
-  memcpy(base::AssumeLittleEndian(&res), *ptr, sizeof(T));
+  memcpy(&res, *ptr, sizeof(T));
   *ptr += sizeof(T);
-  return res;
+  return base::LEToHost(res);
 }
 
 }  // namespace