Pass the starting buffer pointer for the backalloc to _upb_Encode_Field and _upb_Encode_Extension.

PiperOrigin-RevId: 912682505

Author: adazh

upb/wire/encode.c

@@ -848,15 +848,14 @@ upb_EncodeStatus upb_Encode(const upb_Message* msg, const upb_MiniTable* l,
   return _upb_Encode(msg, l, options, arena, buf, size, false);
 }
 
-upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Field)(upb_encstate* e,
+upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Field)(char* ptr, upb_encstate* e,
                                                 const upb_Message* msg,
                                                 const upb_MiniTableField* field,
                                                 char** buf, size_t* size,
                                                 int options) {
   e->options = options;
   e->depth = upb_EncodeOptions_GetEffectiveMaxDepth(options);
 
-  char* ptr = e->alloc.limit;
   if (encode_shouldencode(msg, field)) {
     ptr = encode_field(ptr, e, msg, field);
   }
@@ -866,13 +865,12 @@ upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Field)(upb_encstate* e,
 }
 
 upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Extension)(
-    upb_encstate* e, const upb_MiniTableExtension* ext,
+    char* ptr, upb_encstate* e, const upb_MiniTableExtension* ext,
     upb_MessageValue ext_val, bool is_message_set, char** buf, size_t* size,
     int options) {
   e->options = options;
   e->depth = upb_EncodeOptions_GetEffectiveMaxDepth(options);
 
-  char* ptr = e->alloc.limit;
   ptr = encode_ext(ptr, e, ext, ext_val, is_message_set);
   *size = upb_BackAlloc_Finish(&e->alloc, ptr);
   *buf = ptr;

upb/wire/encode_test.cc

@@ -27,7 +27,8 @@ static void DoEncodeFieldMaxDepthExceeded(jmp_buf err, upb_encstate& e,
                                           const upb_MiniTableField* field,
                                           char*& buf, size_t& size) {
   if (UPB_SETJMP(err) == 0) {
-    UPB_PRIVATE(_upb_Encode_Field)(&e, msg, field, &buf, &size, e.options);
+    UPB_PRIVATE(_upb_Encode_Field)(e.alloc.limit, &e, msg, field, &buf, &size,
+                                   e.options);
     FAIL() << "Should have jumped";
   } else {
     EXPECT_EQ(e.status, kUpb_EncodeStatus_MaxDepthExceeded);
@@ -39,8 +40,8 @@ static void DoEncodeExtensionMaxDepthExceeded(jmp_buf err, upb_encstate& e,
                                               upb_MessageValue ext_val,
                                               char*& buf, size_t& size) {
   if (UPB_SETJMP(err) == 0) {
-    UPB_PRIVATE(_upb_Encode_Extension)(&e, ext, ext_val, false, &buf, &size,
-                                       e.options);
+    UPB_PRIVATE(_upb_Encode_Extension)(e.alloc.limit, &e, ext, ext_val, false,
+                                       &buf, &size, e.options);
     FAIL() << "Should have jumped";
   } else {
     EXPECT_EQ(e.status, kUpb_EncodeStatus_MaxDepthExceeded);
@@ -63,7 +64,7 @@ TEST(EncodeTest, EncodeFieldSuccess) {
   char* buf;
   size_t size;
   upb_EncodeStatus status = UPB_PRIVATE(_upb_Encode_Field)(
-      &e, (upb_Message*)msg, field, &buf, &size, e.options);
+      e.alloc.limit, &e, (upb_Message*)msg, field, &buf, &size, e.options);
   EXPECT_EQ(status, kUpb_EncodeStatus_Ok);
   EXPECT_GT(size, 0);
 
@@ -94,7 +95,7 @@ TEST(EncodeTest, EncodeFieldSuccessEmptyMessage) {
   char* buf;
   size_t size;
   upb_EncodeStatus status = UPB_PRIVATE(_upb_Encode_Field)(
-      &e, (upb_Message*)msg, field, &buf, &size, e.options);
+      e.alloc.limit, &e, (upb_Message*)msg, field, &buf, &size, e.options);
   EXPECT_EQ(status, kUpb_EncodeStatus_Ok);
   EXPECT_EQ(size, 0);
 
@@ -139,7 +140,7 @@ TEST(EncodeTest, EncodeExtensionSuccess) {
   char* buf;
   size_t size;
   upb_EncodeStatus status = UPB_PRIVATE(_upb_Encode_Extension)(
-      &e, ext, ext_val, false, &buf, &size, e.options);
+      e.alloc.limit, &e, ext, ext_val, false, &buf, &size, e.options);
   EXPECT_EQ(status, kUpb_EncodeStatus_Ok);
   EXPECT_GT(size, 0);
 
@@ -175,7 +176,7 @@ TEST(EncodeTest, EncodeExtensionSuccessEmptyMessage) {
   char* buf;
   size_t size;
   upb_EncodeStatus status = UPB_PRIVATE(_upb_Encode_Extension)(
-      &e, ext, ext_val, false, &buf, &size, e.options);
+      e.alloc.limit, &e, ext, ext_val, false, &buf, &size, e.options);
   EXPECT_EQ(status, kUpb_EncodeStatus_Ok);
   EXPECT_GT(size, 0);
 

upb/wire/internal/encoder.h

@@ -51,7 +51,7 @@ UPB_INLINE char* UPB_PRIVATE(_upb_encstate_init)(upb_encstate* e, jmp_buf* err,
 //
 // The caller must clean up the `upb_encstate` by calling
 // `_upb_mapsorter_destroy(&e->sorter)` when done.
-upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Field)(upb_encstate* e,
+upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Field)(char* ptr, upb_encstate* e,
                                                 const upb_Message* msg,
                                                 const upb_MiniTableField* field,
                                                 char** buf, size_t* size,
@@ -62,7 +62,7 @@ upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Field)(upb_encstate* e,
 // The caller must clean up the `upb_encstate` by calling
 // `_upb_mapsorter_destroy(&e->sorter)` when done.
 upb_EncodeStatus UPB_PRIVATE(_upb_Encode_Extension)(
-    upb_encstate* e, const upb_MiniTableExtension* ext,
+    char* ptr, upb_encstate* e, const upb_MiniTableExtension* ext,
     upb_MessageValue ext_val, bool is_message_set, char** buf, size_t* size,
     int options);