Even cleaner implementation that does not modify the grpc_mdelem struct.

15 files changed, 375 insertions, 429 deletions

diff --git a/include/grpc/impl/codegen/grpc_types.h b/include/grpc/impl/codegen/grpc_types.h
index d0f77f977b..b5353c1dea 100644
--- a/include/grpc/impl/codegen/grpc_types.h
+++ b/include/grpc/impl/codegen/grpc_types.h
@@ -438,7 +438,6 @@ typedef struct grpc_metadata {
       There is no need to initialize them, and they will be set to garbage
       during calls to grpc. */
   struct /* internal */ {
-    uint8_t obfuscated_byte;
     void* obfuscated[4];
   } internal_data;
 } grpc_metadata;
diff --git a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
index b20d8d8c69..25b0149393 100644
--- a/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
+++ b/src/core/ext/filters/client_channel/lb_policy/grpclb/grpclb.cc
@@ -352,13 +352,11 @@ class GrpcLb : public LoadBalancingPolicy {
 void* lb_token_copy(void* token) {
   return token == nullptr
              ? nullptr
-             : (void*)GRPC_MDELEM_REF(
-                   (grpc_mdelem{(uintptr_t)token, GRPC_MDINDEX_UNUSED}))
-                   .payload;
+             : (void*)GRPC_MDELEM_REF(grpc_mdelem{(uintptr_t)token}).payload;
 }
 void lb_token_destroy(void* token) {
   if (token != nullptr) {
-    GRPC_MDELEM_UNREF((grpc_mdelem{(uintptr_t)token, GRPC_MDINDEX_UNUSED}));
+    GRPC_MDELEM_UNREF(grpc_mdelem{(uintptr_t)token});
   }
 }
 int lb_token_cmp(void* token1, void* token2) {
diff --git a/src/core/ext/transport/chttp2/transport/hpack_encoder.cc b/src/core/ext/transport/chttp2/transport/hpack_encoder.cc
index 9a5af3712d..eff9b97a8e 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_encoder.cc
+++ b/src/core/ext/transport/chttp2/transport/hpack_encoder.cc
@@ -689,8 +689,8 @@ void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor* c,
   }
   for (size_t i = 0; i < extra_headers_size; ++i) {
     grpc_mdelem md = *extra_headers[i];
-    uint8_t static_index = GRPC_MDINDEX(md);
-    if (static_index != GRPC_MDINDEX_UNUSED) {
+    uint8_t static_index = grpc_mdelem_get_static_hpack_table_index(md);
+    if (static_index) {
       emit_indexed(c, static_index, &st);
     } else {
       hpack_enc(c, md, &st);
@@ -698,8 +698,8 @@ void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor* c,
   }
   grpc_metadata_batch_assert_ok(metadata);
   for (grpc_linked_mdelem* l = metadata->list.head; l; l = l->next) {
-    uint8_t static_index = GRPC_MDINDEX(l->md);
-    if (static_index != GRPC_MDINDEX_UNUSED) {
+    uint8_t static_index = grpc_mdelem_get_static_hpack_table_index(l->md);
+    if (static_index) {
       emit_indexed(c, static_index, &st);
     } else {
       hpack_enc(c, l->md, &st);
diff --git a/src/core/lib/transport/metadata.cc b/src/core/lib/transport/metadata.cc
index c5458d1d56..dfcd2e16d8 100644
--- a/src/core/lib/transport/metadata.cc
+++ b/src/core/lib/transport/metadata.cc
@@ -242,8 +242,7 @@ grpc_mdelem grpc_mdelem_create(
   if (!grpc_slice_is_interned(key) || !grpc_slice_is_interned(value)) {
     if (compatible_external_backing_store != nullptr) {
       return GRPC_MAKE_MDELEM(compatible_external_backing_store,
-                              GRPC_MDELEM_STORAGE_EXTERNAL,
-                              GRPC_MDINDEX_UNUSED);
+                              GRPC_MDELEM_STORAGE_EXTERNAL);
     }
 
     allocated_metadata* allocated =
@@ -262,8 +261,7 @@ grpc_mdelem grpc_mdelem_create(
       gpr_free(value_str);
     }
 #endif
-    return GRPC_MAKE_MDELEM(allocated, GRPC_MDELEM_STORAGE_ALLOCATED,
-                            GRPC_MDINDEX_UNUSED);
+    return GRPC_MAKE_MDELEM(allocated, GRPC_MDELEM_STORAGE_ALLOCATED);
   }
 
   if (GRPC_IS_STATIC_METADATA_STRING(key) &&
@@ -291,8 +289,7 @@ grpc_mdelem grpc_mdelem_create(
     if (grpc_slice_eq(key, md->key) && grpc_slice_eq(value, md->value)) {
       REF_MD_LOCKED(shard, md);
       gpr_mu_unlock(&shard->mu);
-      return GRPC_MAKE_MDELEM(md, GRPC_MDELEM_STORAGE_INTERNED,
-                              GRPC_MDINDEX_UNUSED);
+      return GRPC_MAKE_MDELEM(md, GRPC_MDELEM_STORAGE_INTERNED);
     }
   }
 
@@ -324,8 +321,7 @@ grpc_mdelem grpc_mdelem_create(
 
   gpr_mu_unlock(&shard->mu);
 
-  return GRPC_MAKE_MDELEM(md, GRPC_MDELEM_STORAGE_INTERNED,
-                          GRPC_MDINDEX_UNUSED);
+  return GRPC_MAKE_MDELEM(md, GRPC_MDELEM_STORAGE_INTERNED);
 }
 
 grpc_mdelem grpc_mdelem_from_slices(grpc_slice key, grpc_slice value) {
@@ -364,6 +360,15 @@ size_t grpc_mdelem_get_size_in_hpack_table(grpc_mdelem elem,
   }
 }
 
+uint8_t grpc_mdelem_get_static_hpack_table_index(grpc_mdelem md) {
+  if (GRPC_MDELEM_STORAGE(md) == GRPC_MDELEM_STORAGE_STATIC) {
+    return grpc_hpack_static_mdelem_indices[GRPC_MDELEM_DATA(md) -
+                                            grpc_static_mdelem_table];
+  } else {
+    return 0;
+  }
+}
+
 grpc_mdelem grpc_mdelem_ref(grpc_mdelem gmd DEBUG_ARGS) {
   switch (GRPC_MDELEM_STORAGE(gmd)) {
     case GRPC_MDELEM_STORAGE_EXTERNAL:
diff --git a/src/core/lib/transport/metadata.h b/src/core/lib/transport/metadata.h
index 513ac826ea..37419c9d2f 100644
--- a/src/core/lib/transport/metadata.h
+++ b/src/core/lib/transport/metadata.h
@@ -92,20 +92,17 @@ struct grpc_mdelem {
   /* a grpc_mdelem_data* generally, with the two lower bits signalling memory
      ownership as per grpc_mdelem_data_storage */
   uintptr_t payload;
-  /* The static index of this mdelem. This is equivalent to the
-     mdelem's index into the hpack static table. 0 if unused. */
-  uint8_t static_index;
 };
 
 #define GRPC_MDELEM_DATA(md) ((grpc_mdelem_data*)((md).payload & ~(uintptr_t)3))
 #define GRPC_MDELEM_STORAGE(md) \
   ((grpc_mdelem_data_storage)((md).payload & (uintptr_t)3))
 #ifdef __cplusplus
-#define GRPC_MAKE_MDELEM(data, storage, index) \
-  (grpc_mdelem{((uintptr_t)(data)) | ((uintptr_t)storage), index})
+#define GRPC_MAKE_MDELEM(data, storage) \
+  (grpc_mdelem{((uintptr_t)(data)) | ((uintptr_t)storage)})
 #else
-#define GRPC_MAKE_MDELEM(data, storage, index) \
-  ((grpc_mdelem){((uintptr_t)(data)) | ((uintptr_t)storage), index})
+#define GRPC_MAKE_MDELEM(data, storage) \
+  ((grpc_mdelem){((uintptr_t)(data)) | ((uintptr_t)storage)})
 #endif
 #define GRPC_MDELEM_IS_INTERNED(md)          \
   ((grpc_mdelem_data_storage)((md).payload & \
@@ -131,6 +128,11 @@ bool grpc_mdelem_eq(grpc_mdelem a, grpc_mdelem b);
 size_t grpc_mdelem_get_size_in_hpack_table(grpc_mdelem elem,
                                            bool use_true_binary_metadata);
 
+/* Returns the static hpack table index that corresponds to /a elem. Returns 0
+  if /a elem is not statically stored or if it is not in the static hpack
+  table */
+uint8_t grpc_mdelem_get_static_hpack_table_index(grpc_mdelem md);
+
 /* Mutator and accessor for grpc_mdelem user data. The destructor function
    is used as a type tag and is checked during user_data fetch. */
 void* grpc_mdelem_get_user_data(grpc_mdelem md, void (*if_destroy_func)(void*));
@@ -151,10 +153,8 @@ void grpc_mdelem_unref(grpc_mdelem md);
 
 #define GRPC_MDKEY(md) (GRPC_MDELEM_DATA(md)->key)
 #define GRPC_MDVALUE(md) (GRPC_MDELEM_DATA(md)->value)
-#define GRPC_MDINDEX(md) (md.static_index)
-#define GRPC_MDINDEX_UNUSED 0
 
-#define GRPC_MDNULL GRPC_MAKE_MDELEM(NULL, GRPC_MDELEM_STORAGE_EXTERNAL, 0)
+#define GRPC_MDNULL GRPC_MAKE_MDELEM(NULL, GRPC_MDELEM_STORAGE_EXTERNAL)
 #define GRPC_MDISNULL(md) (GRPC_MDELEM_DATA(md) == NULL)
 
 /* We add 32 bytes of padding as per RFC-7540 section 6.5.2. */
diff --git a/src/core/lib/transport/static_metadata.cc b/src/core/lib/transport/static_metadata.cc
index 240a55e0ab..fdedd41036 100644
--- a/src/core/lib/transport/static_metadata.cc
+++ b/src/core/lib/transport/static_metadata.cc
@@ -334,6 +334,14 @@ const grpc_slice grpc_static_slice_table[GRPC_STATIC_MDSTR_COUNT] = {
     {&grpc_static_metadata_refcounts[104], {{g_bytes + 1126, 21}}},
 };
 
+const uint8_t grpc_hpack_static_mdelem_indices[GRPC_STATIC_MDELEM_COUNT] = {
+    0,  0,  0,  0,  0,  0,  0,  0,  3,  8,  13, 6,  7,  0,  1,  2,  0,  4,
+    5,  9,  10, 11, 12, 14, 15, 0,  16, 17, 18, 19, 20, 21, 22, 23, 24, 25,
+    0,  0,  26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
+    42, 43, 44, 0,  0,  45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
+    58, 59, 60, 61, 0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
+};
+
 uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT] = {
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
@@ -390,7 +398,7 @@ grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b) {
   return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k &&
                  elem_idxs[h] != 255
              ? GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[elem_idxs[h]],
-                                GRPC_MDELEM_STORAGE_STATIC, 0)
+                                GRPC_MDELEM_STORAGE_STATIC)
              : GRPC_MDNULL;
 }
 
diff --git a/src/core/lib/transport/static_metadata.h b/src/core/lib/transport/static_metadata.h
index e4a9e2a414..e5319c4c4d 100644
--- a/src/core/lib/transport/static_metadata.h
+++ b/src/core/lib/transport/static_metadata.h
@@ -262,350 +262,266 @@ extern grpc_slice_refcount
 #define GRPC_STATIC_MDELEM_COUNT 86
 extern grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT];
 extern uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];
-/* "grpc-status": "0" Index="0" */
-#define GRPC_MDELEM_GRPC_STATUS_0                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[0], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-status": "1" Index="0" */
-#define GRPC_MDELEM_GRPC_STATUS_1                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[1], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-status": "2" Index="0" */
-#define GRPC_MDELEM_GRPC_STATUS_2                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[2], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-encoding": "identity" Index="0" */
-#define GRPC_MDELEM_GRPC_ENCODING_IDENTITY                                    \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[3], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-encoding": "gzip" Index="0" */
-#define GRPC_MDELEM_GRPC_ENCODING_GZIP                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[4], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-encoding": "deflate" Index="0" */
-#define GRPC_MDELEM_GRPC_ENCODING_DEFLATE                                     \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[5], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "te": "trailers" Index="0" */
-#define GRPC_MDELEM_TE_TRAILERS                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[6], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "content-type": "application/grpc" Index="0" */
-#define GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC                       \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[7], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* ":method": "POST" Index="3" */
-#define GRPC_MDELEM_METHOD_POST                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[8], GRPC_MDELEM_STORAGE_STATIC, \
-                    3))
-/* ":status": "200" Index="8" */
-#define GRPC_MDELEM_STATUS_200                                                \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[9], GRPC_MDELEM_STORAGE_STATIC, \
-                    8))
-/* ":status": "404" Index="13" */
-#define GRPC_MDELEM_STATUS_404                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[10], GRPC_MDELEM_STORAGE_STATIC, \
-                    13))
-/* ":scheme": "http" Index="6" */
-#define GRPC_MDELEM_SCHEME_HTTP                                                \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[11], GRPC_MDELEM_STORAGE_STATIC, \
-                    6))
-/* ":scheme": "https" Index="7" */
-#define GRPC_MDELEM_SCHEME_HTTPS                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[12], GRPC_MDELEM_STORAGE_STATIC, \
-                    7))
-/* ":scheme": "grpc" Index="0" */
-#define GRPC_MDELEM_SCHEME_GRPC                                                \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[13], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* ":authority": "" Index="1" */
-#define GRPC_MDELEM_AUTHORITY_EMPTY                                            \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[14], GRPC_MDELEM_STORAGE_STATIC, \
-                    1))
-/* ":method": "GET" Index="2" */
-#define GRPC_MDELEM_METHOD_GET                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[15], GRPC_MDELEM_STORAGE_STATIC, \
-                    2))
-/* ":method": "PUT" Index="0" */
-#define GRPC_MDELEM_METHOD_PUT                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[16], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* ":path": "/" Index="4" */
-#define GRPC_MDELEM_PATH_SLASH                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[17], GRPC_MDELEM_STORAGE_STATIC, \
-                    4))
-/* ":path": "/index.html" Index="5" */
-#define GRPC_MDELEM_PATH_SLASH_INDEX_DOT_HTML                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[18], GRPC_MDELEM_STORAGE_STATIC, \
-                    5))
-/* ":status": "204" Index="9" */
-#define GRPC_MDELEM_STATUS_204                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[19], GRPC_MDELEM_STORAGE_STATIC, \
-                    9))
-/* ":status": "206" Index="10" */
-#define GRPC_MDELEM_STATUS_206                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[20], GRPC_MDELEM_STORAGE_STATIC, \
-                    10))
-/* ":status": "304" Index="11" */
-#define GRPC_MDELEM_STATUS_304                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[21], GRPC_MDELEM_STORAGE_STATIC, \
-                    11))
-/* ":status": "400" Index="12" */
-#define GRPC_MDELEM_STATUS_400                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[22], GRPC_MDELEM_STORAGE_STATIC, \
-                    12))
-/* ":status": "500" Index="14" */
-#define GRPC_MDELEM_STATUS_500                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[23], GRPC_MDELEM_STORAGE_STATIC, \
-                    14))
-/* "accept-charset": "" Index="15" */
-#define GRPC_MDELEM_ACCEPT_CHARSET_EMPTY                                       \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[24], GRPC_MDELEM_STORAGE_STATIC, \
-                    15))
-/* "accept-encoding": "" Index="0" */
-#define GRPC_MDELEM_ACCEPT_ENCODING_EMPTY                                      \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[25], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "accept-encoding": "gzip, deflate" Index="16" */
-#define GRPC_MDELEM_ACCEPT_ENCODING_GZIP_COMMA_DEFLATE                         \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[26], GRPC_MDELEM_STORAGE_STATIC, \
-                    16))
-/* "accept-language": "" Index="17" */
-#define GRPC_MDELEM_ACCEPT_LANGUAGE_EMPTY                                      \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[27], GRPC_MDELEM_STORAGE_STATIC, \
-                    17))
-/* "accept-ranges": "" Index="18" */
-#define GRPC_MDELEM_ACCEPT_RANGES_EMPTY                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[28], GRPC_MDELEM_STORAGE_STATIC, \
-                    18))
-/* "accept": "" Index="19" */
-#define GRPC_MDELEM_ACCEPT_EMPTY                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[29], GRPC_MDELEM_STORAGE_STATIC, \
-                    19))
-/* "access-control-allow-origin": "" Index="20" */
-#define GRPC_MDELEM_ACCESS_CONTROL_ALLOW_ORIGIN_EMPTY                          \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[30], GRPC_MDELEM_STORAGE_STATIC, \
-                    20))
-/* "age": "" Index="21" */
-#define GRPC_MDELEM_AGE_EMPTY                                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[31], GRPC_MDELEM_STORAGE_STATIC, \
-                    21))
-/* "allow": "" Index="22" */
-#define GRPC_MDELEM_ALLOW_EMPTY                                                \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[32], GRPC_MDELEM_STORAGE_STATIC, \
-                    22))
-/* "authorization": "" Index="23" */
-#define GRPC_MDELEM_AUTHORIZATION_EMPTY                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[33], GRPC_MDELEM_STORAGE_STATIC, \
-                    23))
-/* "cache-control": "" Index="24" */
-#define GRPC_MDELEM_CACHE_CONTROL_EMPTY                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[34], GRPC_MDELEM_STORAGE_STATIC, \
-                    24))
-/* "content-disposition": "" Index="25" */
-#define GRPC_MDELEM_CONTENT_DISPOSITION_EMPTY                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[35], GRPC_MDELEM_STORAGE_STATIC, \
-                    25))
-/* "content-encoding": "identity" Index="0" */
-#define GRPC_MDELEM_CONTENT_ENCODING_IDENTITY                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[36], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "content-encoding": "gzip" Index="0" */
-#define GRPC_MDELEM_CONTENT_ENCODING_GZIP                                      \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[37], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "content-encoding": "" Index="26" */
-#define GRPC_MDELEM_CONTENT_ENCODING_EMPTY                                     \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[38], GRPC_MDELEM_STORAGE_STATIC, \
-                    26))
-/* "content-language": "" Index="27" */
-#define GRPC_MDELEM_CONTENT_LANGUAGE_EMPTY                                     \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[39], GRPC_MDELEM_STORAGE_STATIC, \
-                    27))
-/* "content-length": "" Index="28" */
-#define GRPC_MDELEM_CONTENT_LENGTH_EMPTY                                       \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[40], GRPC_MDELEM_STORAGE_STATIC, \
-                    28))
-/* "content-location": "" Index="29" */
-#define GRPC_MDELEM_CONTENT_LOCATION_EMPTY                                     \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[41], GRPC_MDELEM_STORAGE_STATIC, \
-                    29))
-/* "content-range": "" Index="30" */
-#define GRPC_MDELEM_CONTENT_RANGE_EMPTY                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[42], GRPC_MDELEM_STORAGE_STATIC, \
-                    30))
-/* "content-type": "" Index="31" */
-#define GRPC_MDELEM_CONTENT_TYPE_EMPTY                                         \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[43], GRPC_MDELEM_STORAGE_STATIC, \
-                    31))
-/* "cookie": "" Index="32" */
-#define GRPC_MDELEM_COOKIE_EMPTY                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[44], GRPC_MDELEM_STORAGE_STATIC, \
-                    32))
-/* "date": "" Index="33" */
-#define GRPC_MDELEM_DATE_EMPTY                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[45], GRPC_MDELEM_STORAGE_STATIC, \
-                    33))
-/* "etag": "" Index="34" */
-#define GRPC_MDELEM_ETAG_EMPTY                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[46], GRPC_MDELEM_STORAGE_STATIC, \
-                    34))
-/* "expect": "" Index="35" */
-#define GRPC_MDELEM_EXPECT_EMPTY                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[47], GRPC_MDELEM_STORAGE_STATIC, \
-                    35))
-/* "expires": "" Index="36" */
-#define GRPC_MDELEM_EXPIRES_EMPTY                                              \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[48], GRPC_MDELEM_STORAGE_STATIC, \
-                    36))
-/* "from": "" Index="37" */
-#define GRPC_MDELEM_FROM_EMPTY                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[49], GRPC_MDELEM_STORAGE_STATIC, \
-                    37))
-/* "host": "" Index="38" */
-#define GRPC_MDELEM_HOST_EMPTY                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[50], GRPC_MDELEM_STORAGE_STATIC, \
-                    38))
-/* "if-match": "" Index="39" */
-#define GRPC_MDELEM_IF_MATCH_EMPTY                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[51], GRPC_MDELEM_STORAGE_STATIC, \
-                    39))
-/* "if-modified-since": "" Index="40" */
-#define GRPC_MDELEM_IF_MODIFIED_SINCE_EMPTY                                    \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[52], GRPC_MDELEM_STORAGE_STATIC, \
-                    40))
-/* "if-none-match": "" Index="41" */
-#define GRPC_MDELEM_IF_NONE_MATCH_EMPTY                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[53], GRPC_MDELEM_STORAGE_STATIC, \
-                    41))
-/* "if-range": "" Index="42" */
-#define GRPC_MDELEM_IF_RANGE_EMPTY                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[54], GRPC_MDELEM_STORAGE_STATIC, \
-                    42))
-/* "if-unmodified-since": "" Index="43" */
-#define GRPC_MDELEM_IF_UNMODIFIED_SINCE_EMPTY                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[55], GRPC_MDELEM_STORAGE_STATIC, \
-                    43))
-/* "last-modified": "" Index="44" */
-#define GRPC_MDELEM_LAST_MODIFIED_EMPTY                                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[56], GRPC_MDELEM_STORAGE_STATIC, \
-                    44))
-/* "lb-token": "" Index="0" */
-#define GRPC_MDELEM_LB_TOKEN_EMPTY                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[57], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "lb-cost-bin": "" Index="0" */
-#define GRPC_MDELEM_LB_COST_BIN_EMPTY                                          \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[58], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "link": "" Index="45" */
-#define GRPC_MDELEM_LINK_EMPTY                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[59], GRPC_MDELEM_STORAGE_STATIC, \
-                    45))
-/* "location": "" Index="46" */
-#define GRPC_MDELEM_LOCATION_EMPTY                                             \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[60], GRPC_MDELEM_STORAGE_STATIC, \
-                    46))
-/* "max-forwards": "" Index="47" */
-#define GRPC_MDELEM_MAX_FORWARDS_EMPTY                                         \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[61], GRPC_MDELEM_STORAGE_STATIC, \
-                    47))
-/* "proxy-authenticate": "" Index="48" */
-#define GRPC_MDELEM_PROXY_AUTHENTICATE_EMPTY                                   \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[62], GRPC_MDELEM_STORAGE_STATIC, \
-                    48))
-/* "proxy-authorization": "" Index="49" */
-#define GRPC_MDELEM_PROXY_AUTHORIZATION_EMPTY                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[63], GRPC_MDELEM_STORAGE_STATIC, \
-                    49))
-/* "range": "" Index="50" */
-#define GRPC_MDELEM_RANGE_EMPTY                                                \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[64], GRPC_MDELEM_STORAGE_STATIC, \
-                    50))
-/* "referer": "" Index="51" */
-#define GRPC_MDELEM_REFERER_EMPTY                                              \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[65], GRPC_MDELEM_STORAGE_STATIC, \
-                    51))
-/* "refresh": "" Index="52" */
-#define GRPC_MDELEM_REFRESH_EMPTY                                              \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[66], GRPC_MDELEM_STORAGE_STATIC, \
-                    52))
-/* "retry-after": "" Index="53" */
-#define GRPC_MDELEM_RETRY_AFTER_EMPTY                                          \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[67], GRPC_MDELEM_STORAGE_STATIC, \
-                    53))
-/* "server": "" Index="54" */
-#define GRPC_MDELEM_SERVER_EMPTY                                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[68], GRPC_MDELEM_STORAGE_STATIC, \
-                    54))
-/* "set-cookie": "" Index="55" */
-#define GRPC_MDELEM_SET_COOKIE_EMPTY                                           \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[69], GRPC_MDELEM_STORAGE_STATIC, \
-                    55))
-/* "strict-transport-security": "" Index="56" */
-#define GRPC_MDELEM_STRICT_TRANSPORT_SECURITY_EMPTY                            \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[70], GRPC_MDELEM_STORAGE_STATIC, \
-                    56))
-/* "transfer-encoding": "" Index="57" */
-#define GRPC_MDELEM_TRANSFER_ENCODING_EMPTY                                    \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[71], GRPC_MDELEM_STORAGE_STATIC, \
-                    57))
-/* "user-agent": "" Index="58" */
-#define GRPC_MDELEM_USER_AGENT_EMPTY                                           \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[72], GRPC_MDELEM_STORAGE_STATIC, \
-                    58))
-/* "vary": "" Index="59" */
-#define GRPC_MDELEM_VARY_EMPTY                                                 \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[73], GRPC_MDELEM_STORAGE_STATIC, \
-                    59))
-/* "via": "" Index="60" */
-#define GRPC_MDELEM_VIA_EMPTY                                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[74], GRPC_MDELEM_STORAGE_STATIC, \
-                    60))
-/* "www-authenticate": "" Index="61" */
-#define GRPC_MDELEM_WWW_AUTHENTICATE_EMPTY                                     \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[75], GRPC_MDELEM_STORAGE_STATIC, \
-                    61))
-/* "grpc-accept-encoding": "identity" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY                              \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[76], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-accept-encoding": "deflate" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE                               \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[77], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-accept-encoding": "identity,deflate" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE                \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[78], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-accept-encoding": "gzip" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_GZIP                                  \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[79], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-accept-encoding": "identity,gzip" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_GZIP                   \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[80], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-accept-encoding": "deflate,gzip" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE_COMMA_GZIP                    \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[81], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "grpc-accept-encoding": "identity,deflate,gzip" Index="0" */
-#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE_COMMA_GZIP     \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[82], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "accept-encoding": "identity" Index="0" */
-#define GRPC_MDELEM_ACCEPT_ENCODING_IDENTITY                                   \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[83], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "accept-encoding": "gzip" Index="0" */
-#define GRPC_MDELEM_ACCEPT_ENCODING_GZIP                                       \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[84], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
-/* "accept-encoding": "identity,gzip" Index="0" */
-#define GRPC_MDELEM_ACCEPT_ENCODING_IDENTITY_COMMA_GZIP                        \
-  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[85], GRPC_MDELEM_STORAGE_STATIC, \
-                    0))
+/* "grpc-status": "0" */
+#define GRPC_MDELEM_GRPC_STATUS_0 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[0], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-status": "1" */
+#define GRPC_MDELEM_GRPC_STATUS_1 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[1], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-status": "2" */
+#define GRPC_MDELEM_GRPC_STATUS_2 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[2], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-encoding": "identity" */
+#define GRPC_MDELEM_GRPC_ENCODING_IDENTITY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[3], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-encoding": "gzip" */
+#define GRPC_MDELEM_GRPC_ENCODING_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[4], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-encoding": "deflate" */
+#define GRPC_MDELEM_GRPC_ENCODING_DEFLATE \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[5], GRPC_MDELEM_STORAGE_STATIC))
+/* "te": "trailers" */
+#define GRPC_MDELEM_TE_TRAILERS \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[6], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-type": "application/grpc" */
+#define GRPC_MDELEM_CONTENT_TYPE_APPLICATION_SLASH_GRPC \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[7], GRPC_MDELEM_STORAGE_STATIC))
+/* ":method": "POST" */
+#define GRPC_MDELEM_METHOD_POST \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[8], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "200" */
+#define GRPC_MDELEM_STATUS_200 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[9], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "404" */
+#define GRPC_MDELEM_STATUS_404 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[10], GRPC_MDELEM_STORAGE_STATIC))
+/* ":scheme": "http" */
+#define GRPC_MDELEM_SCHEME_HTTP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[11], GRPC_MDELEM_STORAGE_STATIC))
+/* ":scheme": "https" */
+#define GRPC_MDELEM_SCHEME_HTTPS \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[12], GRPC_MDELEM_STORAGE_STATIC))
+/* ":scheme": "grpc" */
+#define GRPC_MDELEM_SCHEME_GRPC \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[13], GRPC_MDELEM_STORAGE_STATIC))
+/* ":authority": "" */
+#define GRPC_MDELEM_AUTHORITY_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[14], GRPC_MDELEM_STORAGE_STATIC))
+/* ":method": "GET" */
+#define GRPC_MDELEM_METHOD_GET \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[15], GRPC_MDELEM_STORAGE_STATIC))
+/* ":method": "PUT" */
+#define GRPC_MDELEM_METHOD_PUT \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[16], GRPC_MDELEM_STORAGE_STATIC))
+/* ":path": "/" */
+#define GRPC_MDELEM_PATH_SLASH \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[17], GRPC_MDELEM_STORAGE_STATIC))
+/* ":path": "/index.html" */
+#define GRPC_MDELEM_PATH_SLASH_INDEX_DOT_HTML \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[18], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "204" */
+#define GRPC_MDELEM_STATUS_204 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[19], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "206" */
+#define GRPC_MDELEM_STATUS_206 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[20], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "304" */
+#define GRPC_MDELEM_STATUS_304 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[21], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "400" */
+#define GRPC_MDELEM_STATUS_400 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[22], GRPC_MDELEM_STORAGE_STATIC))
+/* ":status": "500" */
+#define GRPC_MDELEM_STATUS_500 \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[23], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-charset": "" */
+#define GRPC_MDELEM_ACCEPT_CHARSET_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[24], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-encoding": "" */
+#define GRPC_MDELEM_ACCEPT_ENCODING_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[25], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-encoding": "gzip, deflate" */
+#define GRPC_MDELEM_ACCEPT_ENCODING_GZIP_COMMA_DEFLATE \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[26], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-language": "" */
+#define GRPC_MDELEM_ACCEPT_LANGUAGE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[27], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-ranges": "" */
+#define GRPC_MDELEM_ACCEPT_RANGES_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[28], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept": "" */
+#define GRPC_MDELEM_ACCEPT_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[29], GRPC_MDELEM_STORAGE_STATIC))
+/* "access-control-allow-origin": "" */
+#define GRPC_MDELEM_ACCESS_CONTROL_ALLOW_ORIGIN_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[30], GRPC_MDELEM_STORAGE_STATIC))
+/* "age": "" */
+#define GRPC_MDELEM_AGE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[31], GRPC_MDELEM_STORAGE_STATIC))
+/* "allow": "" */
+#define GRPC_MDELEM_ALLOW_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[32], GRPC_MDELEM_STORAGE_STATIC))
+/* "authorization": "" */
+#define GRPC_MDELEM_AUTHORIZATION_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[33], GRPC_MDELEM_STORAGE_STATIC))
+/* "cache-control": "" */
+#define GRPC_MDELEM_CACHE_CONTROL_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[34], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-disposition": "" */
+#define GRPC_MDELEM_CONTENT_DISPOSITION_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[35], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-encoding": "identity" */
+#define GRPC_MDELEM_CONTENT_ENCODING_IDENTITY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[36], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-encoding": "gzip" */
+#define GRPC_MDELEM_CONTENT_ENCODING_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[37], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-encoding": "" */
+#define GRPC_MDELEM_CONTENT_ENCODING_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[38], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-language": "" */
+#define GRPC_MDELEM_CONTENT_LANGUAGE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[39], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-length": "" */
+#define GRPC_MDELEM_CONTENT_LENGTH_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[40], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-location": "" */
+#define GRPC_MDELEM_CONTENT_LOCATION_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[41], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-range": "" */
+#define GRPC_MDELEM_CONTENT_RANGE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[42], GRPC_MDELEM_STORAGE_STATIC))
+/* "content-type": "" */
+#define GRPC_MDELEM_CONTENT_TYPE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[43], GRPC_MDELEM_STORAGE_STATIC))
+/* "cookie": "" */
+#define GRPC_MDELEM_COOKIE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[44], GRPC_MDELEM_STORAGE_STATIC))
+/* "date": "" */
+#define GRPC_MDELEM_DATE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[45], GRPC_MDELEM_STORAGE_STATIC))
+/* "etag": "" */
+#define GRPC_MDELEM_ETAG_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[46], GRPC_MDELEM_STORAGE_STATIC))
+/* "expect": "" */
+#define GRPC_MDELEM_EXPECT_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[47], GRPC_MDELEM_STORAGE_STATIC))
+/* "expires": "" */
+#define GRPC_MDELEM_EXPIRES_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[48], GRPC_MDELEM_STORAGE_STATIC))
+/* "from": "" */
+#define GRPC_MDELEM_FROM_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[49], GRPC_MDELEM_STORAGE_STATIC))
+/* "host": "" */
+#define GRPC_MDELEM_HOST_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[50], GRPC_MDELEM_STORAGE_STATIC))
+/* "if-match": "" */
+#define GRPC_MDELEM_IF_MATCH_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[51], GRPC_MDELEM_STORAGE_STATIC))
+/* "if-modified-since": "" */
+#define GRPC_MDELEM_IF_MODIFIED_SINCE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[52], GRPC_MDELEM_STORAGE_STATIC))
+/* "if-none-match": "" */
+#define GRPC_MDELEM_IF_NONE_MATCH_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[53], GRPC_MDELEM_STORAGE_STATIC))
+/* "if-range": "" */
+#define GRPC_MDELEM_IF_RANGE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[54], GRPC_MDELEM_STORAGE_STATIC))
+/* "if-unmodified-since": "" */
+#define GRPC_MDELEM_IF_UNMODIFIED_SINCE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[55], GRPC_MDELEM_STORAGE_STATIC))
+/* "last-modified": "" */
+#define GRPC_MDELEM_LAST_MODIFIED_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[56], GRPC_MDELEM_STORAGE_STATIC))
+/* "lb-token": "" */
+#define GRPC_MDELEM_LB_TOKEN_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[57], GRPC_MDELEM_STORAGE_STATIC))
+/* "lb-cost-bin": "" */
+#define GRPC_MDELEM_LB_COST_BIN_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[58], GRPC_MDELEM_STORAGE_STATIC))
+/* "link": "" */
+#define GRPC_MDELEM_LINK_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[59], GRPC_MDELEM_STORAGE_STATIC))
+/* "location": "" */
+#define GRPC_MDELEM_LOCATION_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[60], GRPC_MDELEM_STORAGE_STATIC))
+/* "max-forwards": "" */
+#define GRPC_MDELEM_MAX_FORWARDS_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[61], GRPC_MDELEM_STORAGE_STATIC))
+/* "proxy-authenticate": "" */
+#define GRPC_MDELEM_PROXY_AUTHENTICATE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[62], GRPC_MDELEM_STORAGE_STATIC))
+/* "proxy-authorization": "" */
+#define GRPC_MDELEM_PROXY_AUTHORIZATION_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[63], GRPC_MDELEM_STORAGE_STATIC))
+/* "range": "" */
+#define GRPC_MDELEM_RANGE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[64], GRPC_MDELEM_STORAGE_STATIC))
+/* "referer": "" */
+#define GRPC_MDELEM_REFERER_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[65], GRPC_MDELEM_STORAGE_STATIC))
+/* "refresh": "" */
+#define GRPC_MDELEM_REFRESH_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[66], GRPC_MDELEM_STORAGE_STATIC))
+/* "retry-after": "" */
+#define GRPC_MDELEM_RETRY_AFTER_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[67], GRPC_MDELEM_STORAGE_STATIC))
+/* "server": "" */
+#define GRPC_MDELEM_SERVER_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[68], GRPC_MDELEM_STORAGE_STATIC))
+/* "set-cookie": "" */
+#define GRPC_MDELEM_SET_COOKIE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[69], GRPC_MDELEM_STORAGE_STATIC))
+/* "strict-transport-security": "" */
+#define GRPC_MDELEM_STRICT_TRANSPORT_SECURITY_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[70], GRPC_MDELEM_STORAGE_STATIC))
+/* "transfer-encoding": "" */
+#define GRPC_MDELEM_TRANSFER_ENCODING_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[71], GRPC_MDELEM_STORAGE_STATIC))
+/* "user-agent": "" */
+#define GRPC_MDELEM_USER_AGENT_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[72], GRPC_MDELEM_STORAGE_STATIC))
+/* "vary": "" */
+#define GRPC_MDELEM_VARY_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[73], GRPC_MDELEM_STORAGE_STATIC))
+/* "via": "" */
+#define GRPC_MDELEM_VIA_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[74], GRPC_MDELEM_STORAGE_STATIC))
+/* "www-authenticate": "" */
+#define GRPC_MDELEM_WWW_AUTHENTICATE_EMPTY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[75], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "identity" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[76], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "deflate" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[77], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "identity,deflate" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[78], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "gzip" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[79], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "identity,gzip" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[80], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "deflate,gzip" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_DEFLATE_COMMA_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[81], GRPC_MDELEM_STORAGE_STATIC))
+/* "grpc-accept-encoding": "identity,deflate,gzip" */
+#define GRPC_MDELEM_GRPC_ACCEPT_ENCODING_IDENTITY_COMMA_DEFLATE_COMMA_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[82], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-encoding": "identity" */
+#define GRPC_MDELEM_ACCEPT_ENCODING_IDENTITY \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[83], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-encoding": "gzip" */
+#define GRPC_MDELEM_ACCEPT_ENCODING_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[84], GRPC_MDELEM_STORAGE_STATIC))
+/* "accept-encoding": "identity,gzip" */
+#define GRPC_MDELEM_ACCEPT_ENCODING_IDENTITY_COMMA_GZIP \
+  (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[85], GRPC_MDELEM_STORAGE_STATIC))
+
+extern const uint8_t grpc_hpack_static_mdelem_indices[GRPC_STATIC_MDELEM_COUNT];
 
 grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b);
 typedef enum {
@@ -679,11 +595,11 @@ extern const uint8_t grpc_static_accept_encoding_metadata[8];
 #define GRPC_MDELEM_ACCEPT_ENCODING_FOR_ALGORITHMS(algs)                       \
   (GRPC_MAKE_MDELEM(                                                           \
       &grpc_static_mdelem_table[grpc_static_accept_encoding_metadata[(algs)]], \
-      GRPC_MDELEM_STORAGE_STATIC, 0))
+      GRPC_MDELEM_STORAGE_STATIC))
 
 extern const uint8_t grpc_static_accept_stream_encoding_metadata[4];
 #define GRPC_MDELEM_ACCEPT_STREAM_ENCODING_FOR_ALGORITHMS(algs)                \
   (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table                                  \
                         [grpc_static_accept_stream_encoding_metadata[(algs)]], \
-                    GRPC_MDELEM_STORAGE_STATIC, 0))
+                    GRPC_MDELEM_STORAGE_STATIC))
 #endif /* GRPC_CORE_LIB_TRANSPORT_STATIC_METADATA_H */
diff --git a/src/objective-c/tests/CronetUnitTests/CronetUnitTests.m b/src/objective-c/tests/CronetUnitTests/CronetUnitTests.m
index 79cc8071e7..75a669da4d 100644
--- a/src/objective-c/tests/CronetUnitTests/CronetUnitTests.m
+++ b/src/objective-c/tests/CronetUnitTests/CronetUnitTests.m
@@ -140,11 +140,11 @@ grpc_channel_args *add_disable_client_authority_filter_args(grpc_channel_args *a
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {0, {NULL, NULL, NULL, NULL}}},
+                              {{NULL, NULL, NULL, NULL}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {0, {NULL, NULL, NULL, NULL}}}};
+                              {{NULL, NULL, NULL, NULL}}}};
 
   int port = grpc_pick_unused_port_or_die();
   char *addr;
@@ -274,11 +274,11 @@ grpc_channel_args *add_disable_client_authority_filter_args(grpc_channel_args *a
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {0, {NULL, NULL, NULL, NULL}}},
+                              {{NULL, NULL, NULL, NULL}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {0, {NULL, NULL, NULL, NULL}}}};
+                              {{NULL, NULL, NULL, NULL}}}};
 
   int port = grpc_pick_unused_port_or_die();
   char *addr;
diff --git a/test/core/end2end/tests/authority_not_supported.cc b/test/core/end2end/tests/authority_not_supported.cc
index 4ccdb5e72a..01a95e4e10 100644
--- a/test/core/end2end/tests/authority_not_supported.cc
+++ b/test/core/end2end/tests/authority_not_supported.cc
@@ -93,11 +93,11 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_end2end_test_fixture f =
       begin_test(config, "test_with_authority_header", nullptr, nullptr);
   cq_verifier* cqv = cq_verifier_create(f.cq);
diff --git a/test/core/end2end/tests/binary_metadata.cc b/test/core/end2end/tests/binary_metadata.cc
index 2ce050355d..cdf5b1eb94 100644
--- a/test/core/end2end/tests/binary_metadata.cc
+++ b/test/core/end2end/tests/binary_metadata.cc
@@ -101,23 +101,23 @@ static void test_request_response_with_metadata_and_payload(
        grpc_slice_from_static_string(
            "\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc"),
        0,
-       {0, {nullptr, nullptr, nullptr, nullptr}}},
+       {{nullptr, nullptr, nullptr, nullptr}}},
       {grpc_slice_from_static_string("key2-bin"),
        grpc_slice_from_static_string(
            "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d"),
        0,
-       {0, {nullptr, nullptr, nullptr, nullptr}}}};
+       {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_metadata meta_s[2] = {
       {grpc_slice_from_static_string("key3-bin"),
        grpc_slice_from_static_string(
            "\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee"),
        0,
-       {0, {nullptr, nullptr, nullptr, nullptr}}},
+       {{nullptr, nullptr, nullptr, nullptr}}},
       {grpc_slice_from_static_string("key4-bin"),
        grpc_slice_from_static_string(
            "\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff"),
        0,
-       {0, {nullptr, nullptr, nullptr, nullptr}}}};
+       {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_end2end_test_fixture f =
       begin_test(config, "test_request_response_with_metadata_and_payload",
                  nullptr, nullptr);
diff --git a/test/core/end2end/tests/simple_cacheable_request.cc b/test/core/end2end/tests/simple_cacheable_request.cc
index 7493818a27..be6d16ecad 100644
--- a/test/core/end2end/tests/simple_cacheable_request.cc
+++ b/test/core/end2end/tests/simple_cacheable_request.cc
@@ -101,19 +101,19 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_metadata meta_s[2] = {{grpc_slice_from_static_string("key3"),
                               grpc_slice_from_static_string("val3"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key4"),
                               grpc_slice_from_static_string("val4"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_end2end_test_fixture f = begin_test(
       config, "test_cacheable_request_response_with_metadata_and_payload",
       nullptr, nullptr);
diff --git a/test/core/end2end/tests/simple_metadata.cc b/test/core/end2end/tests/simple_metadata.cc
index a9e86bda3a..3e476c2129 100644
--- a/test/core/end2end/tests/simple_metadata.cc
+++ b/test/core/end2end/tests/simple_metadata.cc
@@ -99,19 +99,19 @@ static void test_request_response_with_metadata_and_payload(
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_metadata meta_s[2] = {{grpc_slice_from_static_string("key3"),
                               grpc_slice_from_static_string("val3"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key4"),
                               grpc_slice_from_static_string("val4"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_end2end_test_fixture f =
       begin_test(config, "test_request_response_with_metadata_and_payload",
                  nullptr, nullptr);
diff --git a/test/core/end2end/tests/trailing_metadata.cc b/test/core/end2end/tests/trailing_metadata.cc
index 1fb9683ee5..5cf6f2bb11 100644
--- a/test/core/end2end/tests/trailing_metadata.cc
+++ b/test/core/end2end/tests/trailing_metadata.cc
@@ -99,27 +99,27 @@ static void test_request_response_with_metadata_and_payload(
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_metadata meta_s[2] = {{grpc_slice_from_static_string("key3"),
                               grpc_slice_from_static_string("val3"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key4"),
                               grpc_slice_from_static_string("val4"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_metadata meta_t[2] = {{grpc_slice_from_static_string("key5"),
                               grpc_slice_from_static_string("val5"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}},
+                              {{nullptr, nullptr, nullptr, nullptr}}},
                              {grpc_slice_from_static_string("key6"),
                               grpc_slice_from_static_string("val6"),
                               0,
-                              {0, {nullptr, nullptr, nullptr, nullptr}}}};
+                              {{nullptr, nullptr, nullptr, nullptr}}}};
   grpc_end2end_test_fixture f =
       begin_test(config, "test_request_response_with_metadata_and_payload",
                  nullptr, nullptr);
diff --git a/test/core/transport/metadata_test.cc b/test/core/transport/metadata_test.cc
index 7b064c4f2a..4be34f72d9 100644
--- a/test/core/transport/metadata_test.cc
+++ b/test/core/transport/metadata_test.cc
@@ -350,9 +350,8 @@ static void test_copied_static_metadata(bool dup_key, bool dup_value) {
   grpc_core::ExecCtx exec_ctx;
 
   for (size_t i = 0; i < GRPC_STATIC_MDELEM_COUNT; i++) {
-    grpc_mdelem p =
-        GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[i],
-                         GRPC_MDELEM_STORAGE_STATIC, GRPC_MDINDEX_UNUSED);
+    grpc_mdelem p = GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[i],
+                                     GRPC_MDELEM_STORAGE_STATIC);
     grpc_mdelem q =
         grpc_mdelem_from_slices(maybe_dup(GRPC_MDKEY(p), dup_key),
                                 maybe_dup(GRPC_MDVALUE(p), dup_value));
diff --git a/tools/codegen/core/gen_static_metadata.py b/tools/codegen/core/gen_static_metadata.py
index a1de6e0aa1..784e754091 100755
--- a/tools/codegen/core/gen_static_metadata.py
+++ b/tools/codegen/core/gen_static_metadata.py
@@ -23,10 +23,13 @@ import subprocess
 import re
 import perfection
 
-# configuration: a list of either strings or 2-tuples of strings
-# a single string represents a static grpc_mdstr
-# a 2-tuple represents a static grpc_mdelem (and appropriate grpc_mdstrs will
-# also be created)
+# Configuration: a list of either strings or 2-tuples of strings.
+# A single string represents a static grpc_mdstr.
+# A 2-tuple represents a static grpc_mdelem (and appropriate grpc_mdstrs will
+# also be created).
+# A 3-tuple represents a static grpc_mdelem (and appropriate grpc_mdstrs will
+# also be created), with the last value equivalent to the mdelem's static hpack
+# table index as defined by RFC 7541
 
 CONFIG = [
     # metadata strings
@@ -64,14 +67,14 @@ CONFIG = [
     'gzip',
     'stream/gzip',
     # metadata elements
-    ('grpc-status', '0', 0),
-    ('grpc-status', '1', 0),
-    ('grpc-status', '2', 0),
-    ('grpc-encoding', 'identity', 0),
-    ('grpc-encoding', 'gzip', 0),
-    ('grpc-encoding', 'deflate', 0),
-    ('te', 'trailers', 0),
-    ('content-type', 'application/grpc', 0),
+    ('grpc-status', '0'),
+    ('grpc-status', '1'),
+    ('grpc-status', '2'),
+    ('grpc-encoding', 'identity'),
+    ('grpc-encoding', 'gzip'),
+    ('grpc-encoding', 'deflate'),
+    ('te', 'trailers'),
+    ('content-type', 'application/grpc'),
     (':method', 'POST', 3),
     (':status', '200', 8),
     (':status', '404', 13),
@@ -80,7 +83,7 @@ CONFIG = [
     (':scheme', 'grpc', 0),
     (':authority', '', 1),
     (':method', 'GET', 2),
-    (':method', 'PUT', 0),
+    (':method', 'PUT'),
     (':path', '/', 4),
     (':path', '/index.html', 5),
     (':status', '204', 9),
@@ -89,7 +92,7 @@ CONFIG = [
     (':status', '400', 12),
     (':status', '500', 14),
     ('accept-charset', '', 15),
-    ('accept-encoding', '', 0),
+    ('accept-encoding', ''),
     ('accept-encoding', 'gzip, deflate', 16),
     ('accept-language', '', 17),
     ('accept-ranges', '', 18),
@@ -100,8 +103,8 @@ CONFIG = [
     ('authorization', '', 23),
     ('cache-control', '', 24),
     ('content-disposition', '', 25),
-    ('content-encoding', 'identity', 0),
-    ('content-encoding', 'gzip', 0),
+    ('content-encoding', 'identity'),
+    ('content-encoding', 'gzip'),
     ('content-encoding', '', 26),
     ('content-language', '', 27),
     ('content-length', '', 28),
@@ -121,8 +124,8 @@ CONFIG = [
     ('if-range', '', 42),
     ('if-unmodified-since', '', 43),
     ('last-modified', '', 44),
-    ('lb-token', '', 0),
-    ('lb-cost-bin', '', 0),
+    ('lb-token', ''),
+    ('lb-cost-bin', ''),
     ('link', '', 45),
     ('location', '', 46),
     ('max-forwards', '', 47),
@@ -271,7 +274,7 @@ for mask in range(1, 1 << len(COMPRESSION_ALGORITHMS)):
     val = ','.join(COMPRESSION_ALGORITHMS[alg]
                    for alg in range(0, len(COMPRESSION_ALGORITHMS))
                    if (1 << alg) & mask)
-    elem = ('grpc-accept-encoding', val, 0)
+    elem = ('grpc-accept-encoding', val)
     if val not in all_strs:
         all_strs.append(val)
     if elem not in all_elems:
@@ -283,7 +286,7 @@ for mask in range(1, 1 << len(STREAM_COMPRESSION_ALGORITHMS)):
     val = ','.join(STREAM_COMPRESSION_ALGORITHMS[alg]
                    for alg in range(0, len(STREAM_COMPRESSION_ALGORITHMS))
                    if (1 << alg) & mask)
-    elem = ('accept-encoding', val, 0)
+    elem = ('accept-encoding', val)
     if val not in all_strs:
         all_strs.append(val)
     if elem not in all_elems:
@@ -453,11 +456,28 @@ print >> H, ('extern grpc_mdelem_data '
 print >> H, ('extern uintptr_t '
              'grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT];')
 for i, elem in enumerate(all_elems):
-    print >> H, '/* "%s": "%s" Index="%d" */' % elem
+    print >> H, '/* "%s": "%s" */' % (elem[0], elem[1])
     print >> H, ('#define %s (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[%d], '
-                 'GRPC_MDELEM_STORAGE_STATIC, %d))') % (mangle(elem).upper(), i,
-                                                        elem[2])
+                 'GRPC_MDELEM_STORAGE_STATIC))') % (mangle(elem).upper(), i)
 print >> H
+
+# Print out the chttp2 mapping between static mdelem index and the hpack static
+# table index
+print >> H, ('extern const uint8_t grpc_hpack_static_mdelem_indices['
+             'GRPC_STATIC_MDELEM_COUNT];')
+print >> H
+print >> C, ('const uint8_t grpc_hpack_static_mdelem_indices['
+             'GRPC_STATIC_MDELEM_COUNT] = {')
+indices = ''
+for i, elem in enumerate(all_elems):
+    index = 0
+    if len(elem) == 3:
+        index = elem[2]
+    indices += '%d,' % index
+print >> C, '  %s' % indices
+print >> C, '};'
+print >> C
+
 print >> C, ('uintptr_t grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT] '
              '= {')
 print >> C, '  %s' % ','.join(
@@ -545,13 +565,14 @@ print >> C, 'grpc_mdelem grpc_static_mdelem_for_static_strings(int a, int b) {'
 print >> C, '  if (a == -1 || b == -1) return GRPC_MDNULL;'
 print >> C, '  uint32_t k = (uint32_t)(a * %d + b);' % len(all_strs)
 print >> C, '  uint32_t h = elems_phash(k);'
-print >> C, '  return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k && elem_idxs[h] != 255 ? GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[elem_idxs[h]], GRPC_MDELEM_STORAGE_STATIC, 0) : GRPC_MDNULL;'
+print >> C, '  return h < GPR_ARRAY_SIZE(elem_keys) && elem_keys[h] == k && elem_idxs[h] != 255 ? GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[elem_idxs[h]], GRPC_MDELEM_STORAGE_STATIC) : GRPC_MDNULL;'
 print >> C, '}'
 print >> C
 
 print >> C, 'grpc_mdelem_data grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT] = {'
-for a, b, c in all_elems:
-    print >> C, '{%s,%s},' % (slice_def(str_idx(a)), slice_def(str_idx(b)))
+for i, elem in enumerate(all_elems):
+    print >> C, '{%s,%s},' % (slice_def(str_idx(elem[0])),
+                              slice_def(str_idx(elem[1])))
 print >> C, '};'
 
 print >> H, 'typedef enum {'
@@ -588,7 +609,7 @@ print >> C, '0,%s' % ','.join('%d' % md_idx(elem) for elem in compression_elems)
 print >> C, '};'
 print >> C
 
-print >> H, '#define GRPC_MDELEM_ACCEPT_ENCODING_FOR_ALGORITHMS(algs) (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[grpc_static_accept_encoding_metadata[(algs)]], GRPC_MDELEM_STORAGE_STATIC, 0))'
+print >> H, '#define GRPC_MDELEM_ACCEPT_ENCODING_FOR_ALGORITHMS(algs) (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[grpc_static_accept_encoding_metadata[(algs)]], GRPC_MDELEM_STORAGE_STATIC))'
 print >> H
 
 print >> H, 'extern const uint8_t grpc_static_accept_stream_encoding_metadata[%d];' % (
@@ -599,7 +620,7 @@ print >> C, '0,%s' % ','.join(
     '%d' % md_idx(elem) for elem in stream_compression_elems)
 print >> C, '};'
 
-print >> H, '#define GRPC_MDELEM_ACCEPT_STREAM_ENCODING_FOR_ALGORITHMS(algs) (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[grpc_static_accept_stream_encoding_metadata[(algs)]], GRPC_MDELEM_STORAGE_STATIC, 0))'
+print >> H, '#define GRPC_MDELEM_ACCEPT_STREAM_ENCODING_FOR_ALGORITHMS(algs) (GRPC_MAKE_MDELEM(&grpc_static_mdelem_table[grpc_static_accept_stream_encoding_metadata[(algs)]], GRPC_MDELEM_STORAGE_STATIC))'
 
 print >> H, '#endif /* GRPC_CORE_LIB_TRANSPORT_STATIC_METADATA_H */'