--- /dev/null
+/*
+** protobuf decoder bytecode compiler
+**
+** Code to compile a upb::Handlers into bytecode for decoding a protobuf
+** according to that specific schema and destination handlers.
+**
+** Bytecode definition is in decoder.int.h.
+*/
+
+#include <stdarg.h>
+#include "upb/pb/decoder.int.h"
+#include "upb/pb/varint.int.h"
+
+#ifdef UPB_DUMP_BYTECODE
+#include <stdio.h>
+#endif
+
+#include "upb/port_def.inc"
+
+#define MAXLABEL 5
+#define EMPTYLABEL -1
+
+/* upb_pbdecodermethod ********************************************************/
+
+static void freemethod(upb_pbdecodermethod *method) {
+ upb_inttable_uninit(&method->dispatch);
+ upb_gfree(method);
+}
+
+static upb_pbdecodermethod *newmethod(const upb_handlers *dest_handlers,
+ mgroup *group) {
+ upb_pbdecodermethod *ret = upb_gmalloc(sizeof(*ret));
+ upb_byteshandler_init(&ret->input_handler_);
+
+ ret->group = group;
+ ret->dest_handlers_ = dest_handlers;
+ upb_inttable_init(&ret->dispatch, UPB_CTYPE_UINT64);
+
+ return ret;
+}
+
+const upb_handlers *upb_pbdecodermethod_desthandlers(
+ const upb_pbdecodermethod *m) {
+ return m->dest_handlers_;
+}
+
+const upb_byteshandler *upb_pbdecodermethod_inputhandler(
+ const upb_pbdecodermethod *m) {
+ return &m->input_handler_;
+}
+
+bool upb_pbdecodermethod_isnative(const upb_pbdecodermethod *m) {
+ return m->is_native_;
+}
+
+
+/* mgroup *********************************************************************/
+
+static void freegroup(mgroup *g) {
+ upb_inttable_iter i;
+
+ upb_inttable_begin(&i, &g->methods);
+ for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
+ freemethod(upb_value_getptr(upb_inttable_iter_value(&i)));
+ }
+
+ upb_inttable_uninit(&g->methods);
+ upb_gfree(g->bytecode);
+ upb_gfree(g);
+}
+
+mgroup *newgroup(void) {
+ mgroup *g = upb_gmalloc(sizeof(*g));
+ upb_inttable_init(&g->methods, UPB_CTYPE_PTR);
+ g->bytecode = NULL;
+ g->bytecode_end = NULL;
+ return g;
+}
+
+
+/* bytecode compiler **********************************************************/
+
+/* Data used only at compilation time. */
+typedef struct {
+ mgroup *group;
+
+ uint32_t *pc;
+ int fwd_labels[MAXLABEL];
+ int back_labels[MAXLABEL];
+
+ /* For fields marked "lazy", parse them lazily or eagerly? */
+ bool lazy;
+} compiler;
+
+static compiler *newcompiler(mgroup *group, bool lazy) {
+ compiler *ret = upb_gmalloc(sizeof(*ret));
+ int i;
+
+ ret->group = group;
+ ret->lazy = lazy;
+ for (i = 0; i < MAXLABEL; i++) {
+ ret->fwd_labels[i] = EMPTYLABEL;
+ ret->back_labels[i] = EMPTYLABEL;
+ }
+ return ret;
+}
+
+static void freecompiler(compiler *c) {
+ upb_gfree(c);
+}
+
+const size_t ptr_words = sizeof(void*) / sizeof(uint32_t);
+
+/* How many words an instruction is. */
+static int instruction_len(uint32_t instr) {
+ switch (getop(instr)) {
+ case OP_SETDISPATCH: return 1 + ptr_words;
+ case OP_TAGN: return 3;
+ case OP_SETBIGGROUPNUM: return 2;
+ default: return 1;
+ }
+}
+
+bool op_has_longofs(int32_t instruction) {
+ switch (getop(instruction)) {
+ case OP_CALL:
+ case OP_BRANCH:
+ case OP_CHECKDELIM:
+ return true;
+ /* The "tag" instructions only have 8 bytes available for the jump target,
+ * but that is ok because these opcodes only require short jumps. */
+ case OP_TAG1:
+ case OP_TAG2:
+ case OP_TAGN:
+ return false;
+ default:
+ UPB_ASSERT(false);
+ return false;
+ }
+}
+
+static int32_t getofs(uint32_t instruction) {
+ if (op_has_longofs(instruction)) {
+ return (int32_t)instruction >> 8;
+ } else {
+ return (int8_t)(instruction >> 8);
+ }
+}
+
+static void setofs(uint32_t *instruction, int32_t ofs) {
+ if (op_has_longofs(*instruction)) {
+ *instruction = getop(*instruction) | (uint32_t)ofs << 8;
+ } else {
+ *instruction = (*instruction & ~0xff00) | ((ofs & 0xff) << 8);
+ }
+ UPB_ASSERT(getofs(*instruction) == ofs); /* Would fail in cases of overflow. */
+}
+
+static uint32_t pcofs(compiler *c) { return c->pc - c->group->bytecode; }
+
+/* Defines a local label at the current PC location. All previous forward
+ * references are updated to point to this location. The location is noted
+ * for any future backward references. */
+static void label(compiler *c, unsigned int label) {
+ int val;
+ uint32_t *codep;
+
+ UPB_ASSERT(label < MAXLABEL);
+ val = c->fwd_labels[label];
+ codep = (val == EMPTYLABEL) ? NULL : c->group->bytecode + val;
+ while (codep) {
+ int ofs = getofs(*codep);
+ setofs(codep, c->pc - codep - instruction_len(*codep));
+ codep = ofs ? codep + ofs : NULL;
+ }
+ c->fwd_labels[label] = EMPTYLABEL;
+ c->back_labels[label] = pcofs(c);
+}
+
+/* Creates a reference to a numbered label; either a forward reference
+ * (positive arg) or backward reference (negative arg). For forward references
+ * the value returned now is actually a "next" pointer into a linked list of all
+ * instructions that use this label and will be patched later when the label is
+ * defined with label().
+ *
+ * The returned value is the offset that should be written into the instruction.
+ */
+static int32_t labelref(compiler *c, int label) {
+ UPB_ASSERT(label < MAXLABEL);
+ if (label == LABEL_DISPATCH) {
+ /* No resolving required. */
+ return 0;
+ } else if (label < 0) {
+ /* Backward local label. Relative to the next instruction. */
+ uint32_t from = (c->pc + 1) - c->group->bytecode;
+ return c->back_labels[-label] - from;
+ } else {
+ /* Forward local label: prepend to (possibly-empty) linked list. */
+ int *lptr = &c->fwd_labels[label];
+ int32_t ret = (*lptr == EMPTYLABEL) ? 0 : *lptr - pcofs(c);
+ *lptr = pcofs(c);
+ return ret;
+ }
+}
+
+static void put32(compiler *c, uint32_t v) {
+ mgroup *g = c->group;
+ if (c->pc == g->bytecode_end) {
+ int ofs = pcofs(c);
+ size_t oldsize = g->bytecode_end - g->bytecode;
+ size_t newsize = UPB_MAX(oldsize * 2, 64);
+ /* TODO(haberman): handle OOM. */
+ g->bytecode = upb_grealloc(g->bytecode, oldsize * sizeof(uint32_t),
+ newsize * sizeof(uint32_t));
+ g->bytecode_end = g->bytecode + newsize;
+ c->pc = g->bytecode + ofs;
+ }
+ *c->pc++ = v;
+}
+
+static void putop(compiler *c, int op, ...) {
+ va_list ap;
+ va_start(ap, op);
+
+ switch (op) {
+ case OP_SETDISPATCH: {
+ uintptr_t ptr = (uintptr_t)va_arg(ap, void*);
+ put32(c, OP_SETDISPATCH);
+ put32(c, ptr);
+ if (sizeof(uintptr_t) > sizeof(uint32_t))
+ put32(c, (uint64_t)ptr >> 32);
+ break;
+ }
+ case OP_STARTMSG:
+ case OP_ENDMSG:
+ case OP_PUSHLENDELIM:
+ case OP_POP:
+ case OP_SETDELIM:
+ case OP_HALT:
+ case OP_RET:
+ case OP_DISPATCH:
+ put32(c, op);
+ break;
+ case OP_PARSE_DOUBLE:
+ case OP_PARSE_FLOAT:
+ case OP_PARSE_INT64:
+ case OP_PARSE_UINT64:
+ case OP_PARSE_INT32:
+ case OP_PARSE_FIXED64:
+ case OP_PARSE_FIXED32:
+ case OP_PARSE_BOOL:
+ case OP_PARSE_UINT32:
+ case OP_PARSE_SFIXED32:
+ case OP_PARSE_SFIXED64:
+ case OP_PARSE_SINT32:
+ case OP_PARSE_SINT64:
+ case OP_STARTSEQ:
+ case OP_ENDSEQ:
+ case OP_STARTSUBMSG:
+ case OP_ENDSUBMSG:
+ case OP_STARTSTR:
+ case OP_STRING:
+ case OP_ENDSTR:
+ case OP_PUSHTAGDELIM:
+ put32(c, op | va_arg(ap, upb_selector_t) << 8);
+ break;
+ case OP_SETBIGGROUPNUM:
+ put32(c, op);
+ put32(c, va_arg(ap, int));
+ break;
+ case OP_CALL: {
+ const upb_pbdecodermethod *method = va_arg(ap, upb_pbdecodermethod *);
+ put32(c, op | (method->code_base.ofs - (pcofs(c) + 1)) << 8);
+ break;
+ }
+ case OP_CHECKDELIM:
+ case OP_BRANCH: {
+ uint32_t instruction = op;
+ int label = va_arg(ap, int);
+ setofs(&instruction, labelref(c, label));
+ put32(c, instruction);
+ break;
+ }
+ case OP_TAG1:
+ case OP_TAG2: {
+ int label = va_arg(ap, int);
+ uint64_t tag = va_arg(ap, uint64_t);
+ uint32_t instruction = op | (tag << 16);
+ UPB_ASSERT(tag <= 0xffff);
+ setofs(&instruction, labelref(c, label));
+ put32(c, instruction);
+ break;
+ }
+ case OP_TAGN: {
+ int label = va_arg(ap, int);
+ uint64_t tag = va_arg(ap, uint64_t);
+ uint32_t instruction = op | (upb_value_size(tag) << 16);
+ setofs(&instruction, labelref(c, label));
+ put32(c, instruction);
+ put32(c, tag);
+ put32(c, tag >> 32);
+ break;
+ }
+ }
+
+ va_end(ap);
+}
+
+#if defined(UPB_DUMP_BYTECODE)
+
+const char *upb_pbdecoder_getopname(unsigned int op) {
+#define QUOTE(x) #x
+#define EXPAND_AND_QUOTE(x) QUOTE(x)
+#define OPNAME(x) OP_##x
+#define OP(x) case OPNAME(x): return EXPAND_AND_QUOTE(OPNAME(x));
+#define T(x) OP(PARSE_##x)
+ /* Keep in sync with list in decoder.int.h. */
+ switch ((opcode)op) {
+ T(DOUBLE) T(FLOAT) T(INT64) T(UINT64) T(INT32) T(FIXED64) T(FIXED32)
+ T(BOOL) T(UINT32) T(SFIXED32) T(SFIXED64) T(SINT32) T(SINT64)
+ OP(STARTMSG) OP(ENDMSG) OP(STARTSEQ) OP(ENDSEQ) OP(STARTSUBMSG)
+ OP(ENDSUBMSG) OP(STARTSTR) OP(STRING) OP(ENDSTR) OP(CALL) OP(RET)
+ OP(PUSHLENDELIM) OP(PUSHTAGDELIM) OP(SETDELIM) OP(CHECKDELIM)
+ OP(BRANCH) OP(TAG1) OP(TAG2) OP(TAGN) OP(SETDISPATCH) OP(POP)
+ OP(SETBIGGROUPNUM) OP(DISPATCH) OP(HALT)
+ }
+ return "<unknown op>";
+#undef OP
+#undef T
+}
+
+#endif
+
+#ifdef UPB_DUMP_BYTECODE
+
+static void dumpbc(uint32_t *p, uint32_t *end, FILE *f) {
+
+ uint32_t *begin = p;
+
+ while (p < end) {
+ fprintf(f, "%p %8tx", p, p - begin);
+ uint32_t instr = *p++;
+ uint8_t op = getop(instr);
+ fprintf(f, " %s", upb_pbdecoder_getopname(op));
+ switch ((opcode)op) {
+ case OP_SETDISPATCH: {
+ const upb_inttable *dispatch;
+ memcpy(&dispatch, p, sizeof(void*));
+ p += ptr_words;
+ const upb_pbdecodermethod *method =
+ (void *)((char *)dispatch -
+ offsetof(upb_pbdecodermethod, dispatch));
+ fprintf(f, " %s", upb_msgdef_fullname(
+ upb_handlers_msgdef(method->dest_handlers_)));
+ break;
+ }
+ case OP_DISPATCH:
+ case OP_STARTMSG:
+ case OP_ENDMSG:
+ case OP_PUSHLENDELIM:
+ case OP_POP:
+ case OP_SETDELIM:
+ case OP_HALT:
+ case OP_RET:
+ break;
+ case OP_PARSE_DOUBLE:
+ case OP_PARSE_FLOAT:
+ case OP_PARSE_INT64:
+ case OP_PARSE_UINT64:
+ case OP_PARSE_INT32:
+ case OP_PARSE_FIXED64:
+ case OP_PARSE_FIXED32:
+ case OP_PARSE_BOOL:
+ case OP_PARSE_UINT32:
+ case OP_PARSE_SFIXED32:
+ case OP_PARSE_SFIXED64:
+ case OP_PARSE_SINT32:
+ case OP_PARSE_SINT64:
+ case OP_STARTSEQ:
+ case OP_ENDSEQ:
+ case OP_STARTSUBMSG:
+ case OP_ENDSUBMSG:
+ case OP_STARTSTR:
+ case OP_STRING:
+ case OP_ENDSTR:
+ case OP_PUSHTAGDELIM:
+ fprintf(f, " %d", instr >> 8);
+ break;
+ case OP_SETBIGGROUPNUM:
+ fprintf(f, " %d", *p++);
+ break;
+ case OP_CHECKDELIM:
+ case OP_CALL:
+ case OP_BRANCH:
+ fprintf(f, " =>0x%tx", p + getofs(instr) - begin);
+ break;
+ case OP_TAG1:
+ case OP_TAG2: {
+ fprintf(f, " tag:0x%x", instr >> 16);
+ if (getofs(instr)) {
+ fprintf(f, " =>0x%tx", p + getofs(instr) - begin);
+ }
+ break;
+ }
+ case OP_TAGN: {
+ uint64_t tag = *p++;
+ tag |= (uint64_t)*p++ << 32;
+ fprintf(f, " tag:0x%llx", (long long)tag);
+ fprintf(f, " n:%d", instr >> 16);
+ if (getofs(instr)) {
+ fprintf(f, " =>0x%tx", p + getofs(instr) - begin);
+ }
+ break;
+ }
+ }
+ fputs("\n", f);
+ }
+}
+
+#endif
+
+static uint64_t get_encoded_tag(const upb_fielddef *f, int wire_type) {
+ uint32_t tag = (upb_fielddef_number(f) << 3) | wire_type;
+ uint64_t encoded_tag = upb_vencode32(tag);
+ /* No tag should be greater than 5 bytes. */
+ UPB_ASSERT(encoded_tag <= 0xffffffffff);
+ return encoded_tag;
+}
+
+static void putchecktag(compiler *c, const upb_fielddef *f,
+ int wire_type, int dest) {
+ uint64_t tag = get_encoded_tag(f, wire_type);
+ switch (upb_value_size(tag)) {
+ case 1:
+ putop(c, OP_TAG1, dest, tag);
+ break;
+ case 2:
+ putop(c, OP_TAG2, dest, tag);
+ break;
+ default:
+ putop(c, OP_TAGN, dest, tag);
+ break;
+ }
+}
+
+static upb_selector_t getsel(const upb_fielddef *f, upb_handlertype_t type) {
+ upb_selector_t selector;
+ bool ok = upb_handlers_getselector(f, type, &selector);
+ UPB_ASSERT(ok);
+ return selector;
+}
+
+/* Takes an existing, primary dispatch table entry and repacks it with a
+ * different alternate wire type. Called when we are inserting a secondary
+ * dispatch table entry for an alternate wire type. */
+static uint64_t repack(uint64_t dispatch, int new_wt2) {
+ uint64_t ofs;
+ uint8_t wt1;
+ uint8_t old_wt2;
+ upb_pbdecoder_unpackdispatch(dispatch, &ofs, &wt1, &old_wt2);
+ UPB_ASSERT(old_wt2 == NO_WIRE_TYPE); /* wt2 should not be set yet. */
+ return upb_pbdecoder_packdispatch(ofs, wt1, new_wt2);
+}
+
+/* Marks the current bytecode position as the dispatch target for this message,
+ * field, and wire type. */
+static void dispatchtarget(compiler *c, upb_pbdecodermethod *method,
+ const upb_fielddef *f, int wire_type) {
+ /* Offset is relative to msg base. */
+ uint64_t ofs = pcofs(c) - method->code_base.ofs;
+ uint32_t fn = upb_fielddef_number(f);
+ upb_inttable *d = &method->dispatch;
+ upb_value v;
+ if (upb_inttable_remove(d, fn, &v)) {
+ /* TODO: prioritize based on packed setting in .proto file. */
+ uint64_t repacked = repack(upb_value_getuint64(v), wire_type);
+ upb_inttable_insert(d, fn, upb_value_uint64(repacked));
+ upb_inttable_insert(d, fn + UPB_MAX_FIELDNUMBER, upb_value_uint64(ofs));
+ } else {
+ uint64_t val = upb_pbdecoder_packdispatch(ofs, wire_type, NO_WIRE_TYPE);
+ upb_inttable_insert(d, fn, upb_value_uint64(val));
+ }
+}
+
+static void putpush(compiler *c, const upb_fielddef *f) {
+ if (upb_fielddef_descriptortype(f) == UPB_DESCRIPTOR_TYPE_MESSAGE) {
+ putop(c, OP_PUSHLENDELIM);
+ } else {
+ uint32_t fn = upb_fielddef_number(f);
+ if (fn >= 1 << 24) {
+ putop(c, OP_PUSHTAGDELIM, 0);
+ putop(c, OP_SETBIGGROUPNUM, fn);
+ } else {
+ putop(c, OP_PUSHTAGDELIM, fn);
+ }
+ }
+}
+
+static upb_pbdecodermethod *find_submethod(const compiler *c,
+ const upb_pbdecodermethod *method,
+ const upb_fielddef *f) {
+ const upb_handlers *sub =
+ upb_handlers_getsubhandlers(method->dest_handlers_, f);
+ upb_value v;
+ return upb_inttable_lookupptr(&c->group->methods, sub, &v)
+ ? upb_value_getptr(v)
+ : NULL;
+}
+
+static void putsel(compiler *c, opcode op, upb_selector_t sel,
+ const upb_handlers *h) {
+ if (upb_handlers_gethandler(h, sel, NULL)) {
+ putop(c, op, sel);
+ }
+}
+
+/* Puts an opcode to call a callback, but only if a callback actually exists for
+ * this field and handler type. */
+static void maybeput(compiler *c, opcode op, const upb_handlers *h,
+ const upb_fielddef *f, upb_handlertype_t type) {
+ putsel(c, op, getsel(f, type), h);
+}
+
+static bool haslazyhandlers(const upb_handlers *h, const upb_fielddef *f) {
+ if (!upb_fielddef_lazy(f))
+ return false;
+
+ return upb_handlers_gethandler(h, getsel(f, UPB_HANDLER_STARTSTR), NULL) ||
+ upb_handlers_gethandler(h, getsel(f, UPB_HANDLER_STRING), NULL) ||
+ upb_handlers_gethandler(h, getsel(f, UPB_HANDLER_ENDSTR), NULL);
+}
+
+
+/* bytecode compiler code generation ******************************************/
+
+/* Symbolic names for our local labels. */
+#define LABEL_LOOPSTART 1 /* Top of a repeated field loop. */
+#define LABEL_LOOPBREAK 2 /* To jump out of a repeated loop */
+#define LABEL_FIELD 3 /* Jump backward to find the most recent field. */
+#define LABEL_ENDMSG 4 /* To reach the OP_ENDMSG instr for this msg. */
+
+/* Generates bytecode to parse a single non-lazy message field. */
+static void generate_msgfield(compiler *c, const upb_fielddef *f,
+ upb_pbdecodermethod *method) {
+ const upb_handlers *h = upb_pbdecodermethod_desthandlers(method);
+ const upb_pbdecodermethod *sub_m = find_submethod(c, method, f);
+ int wire_type;
+
+ if (!sub_m) {
+ /* Don't emit any code for this field at all; it will be parsed as an
+ * unknown field.
+ *
+ * TODO(haberman): we should change this to parse it as a string field
+ * instead. It will probably be faster, but more importantly, once we
+ * start vending unknown fields, a field shouldn't be treated as unknown
+ * just because it doesn't have subhandlers registered. */
+ return;
+ }
+
+ label(c, LABEL_FIELD);
+
+ wire_type =
+ (upb_fielddef_descriptortype(f) == UPB_DESCRIPTOR_TYPE_MESSAGE)
+ ? UPB_WIRE_TYPE_DELIMITED
+ : UPB_WIRE_TYPE_START_GROUP;
+
+ if (upb_fielddef_isseq(f)) {
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ putchecktag(c, f, wire_type, LABEL_DISPATCH);
+ dispatchtarget(c, method, f, wire_type);
+ putop(c, OP_PUSHTAGDELIM, 0);
+ putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ));
+ label(c, LABEL_LOOPSTART);
+ putpush(c, f);
+ putop(c, OP_STARTSUBMSG, getsel(f, UPB_HANDLER_STARTSUBMSG));
+ putop(c, OP_CALL, sub_m);
+ putop(c, OP_POP);
+ maybeput(c, OP_ENDSUBMSG, h, f, UPB_HANDLER_ENDSUBMSG);
+ if (wire_type == UPB_WIRE_TYPE_DELIMITED) {
+ putop(c, OP_SETDELIM);
+ }
+ putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
+ putchecktag(c, f, wire_type, LABEL_LOOPBREAK);
+ putop(c, OP_BRANCH, -LABEL_LOOPSTART);
+ label(c, LABEL_LOOPBREAK);
+ putop(c, OP_POP);
+ maybeput(c, OP_ENDSEQ, h, f, UPB_HANDLER_ENDSEQ);
+ } else {
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ putchecktag(c, f, wire_type, LABEL_DISPATCH);
+ dispatchtarget(c, method, f, wire_type);
+ putpush(c, f);
+ putop(c, OP_STARTSUBMSG, getsel(f, UPB_HANDLER_STARTSUBMSG));
+ putop(c, OP_CALL, sub_m);
+ putop(c, OP_POP);
+ maybeput(c, OP_ENDSUBMSG, h, f, UPB_HANDLER_ENDSUBMSG);
+ if (wire_type == UPB_WIRE_TYPE_DELIMITED) {
+ putop(c, OP_SETDELIM);
+ }
+ }
+}
+
+/* Generates bytecode to parse a single string or lazy submessage field. */
+static void generate_delimfield(compiler *c, const upb_fielddef *f,
+ upb_pbdecodermethod *method) {
+ const upb_handlers *h = upb_pbdecodermethod_desthandlers(method);
+
+ label(c, LABEL_FIELD);
+ if (upb_fielddef_isseq(f)) {
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_DISPATCH);
+ dispatchtarget(c, method, f, UPB_WIRE_TYPE_DELIMITED);
+ putop(c, OP_PUSHTAGDELIM, 0);
+ putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ));
+ label(c, LABEL_LOOPSTART);
+ putop(c, OP_PUSHLENDELIM);
+ putop(c, OP_STARTSTR, getsel(f, UPB_HANDLER_STARTSTR));
+ /* Need to emit even if no handler to skip past the string. */
+ putop(c, OP_STRING, getsel(f, UPB_HANDLER_STRING));
+ maybeput(c, OP_ENDSTR, h, f, UPB_HANDLER_ENDSTR);
+ putop(c, OP_POP);
+ putop(c, OP_SETDELIM);
+ putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
+ putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_LOOPBREAK);
+ putop(c, OP_BRANCH, -LABEL_LOOPSTART);
+ label(c, LABEL_LOOPBREAK);
+ putop(c, OP_POP);
+ maybeput(c, OP_ENDSEQ, h, f, UPB_HANDLER_ENDSEQ);
+ } else {
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_DISPATCH);
+ dispatchtarget(c, method, f, UPB_WIRE_TYPE_DELIMITED);
+ putop(c, OP_PUSHLENDELIM);
+ putop(c, OP_STARTSTR, getsel(f, UPB_HANDLER_STARTSTR));
+ putop(c, OP_STRING, getsel(f, UPB_HANDLER_STRING));
+ maybeput(c, OP_ENDSTR, h, f, UPB_HANDLER_ENDSTR);
+ putop(c, OP_POP);
+ putop(c, OP_SETDELIM);
+ }
+}
+
+/* Generates bytecode to parse a single primitive field. */
+static void generate_primitivefield(compiler *c, const upb_fielddef *f,
+ upb_pbdecodermethod *method) {
+ const upb_handlers *h = upb_pbdecodermethod_desthandlers(method);
+ upb_descriptortype_t descriptor_type = upb_fielddef_descriptortype(f);
+ opcode parse_type;
+ upb_selector_t sel;
+ int wire_type;
+
+ label(c, LABEL_FIELD);
+
+ /* From a decoding perspective, ENUM is the same as INT32. */
+ if (descriptor_type == UPB_DESCRIPTOR_TYPE_ENUM)
+ descriptor_type = UPB_DESCRIPTOR_TYPE_INT32;
+
+ parse_type = (opcode)descriptor_type;
+
+ /* TODO(haberman): generate packed or non-packed first depending on "packed"
+ * setting in the fielddef. This will favor (in speed) whichever was
+ * specified. */
+
+ UPB_ASSERT((int)parse_type >= 0 && parse_type <= OP_MAX);
+ sel = getsel(f, upb_handlers_getprimitivehandlertype(f));
+ wire_type = upb_pb_native_wire_types[upb_fielddef_descriptortype(f)];
+ if (upb_fielddef_isseq(f)) {
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ putchecktag(c, f, UPB_WIRE_TYPE_DELIMITED, LABEL_DISPATCH);
+ dispatchtarget(c, method, f, UPB_WIRE_TYPE_DELIMITED);
+ putop(c, OP_PUSHLENDELIM);
+ putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ)); /* Packed */
+ label(c, LABEL_LOOPSTART);
+ putop(c, parse_type, sel);
+ putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
+ putop(c, OP_BRANCH, -LABEL_LOOPSTART);
+ dispatchtarget(c, method, f, wire_type);
+ putop(c, OP_PUSHTAGDELIM, 0);
+ putop(c, OP_STARTSEQ, getsel(f, UPB_HANDLER_STARTSEQ)); /* Non-packed */
+ label(c, LABEL_LOOPSTART);
+ putop(c, parse_type, sel);
+ putop(c, OP_CHECKDELIM, LABEL_LOOPBREAK);
+ putchecktag(c, f, wire_type, LABEL_LOOPBREAK);
+ putop(c, OP_BRANCH, -LABEL_LOOPSTART);
+ label(c, LABEL_LOOPBREAK);
+ putop(c, OP_POP); /* Packed and non-packed join. */
+ maybeput(c, OP_ENDSEQ, h, f, UPB_HANDLER_ENDSEQ);
+ putop(c, OP_SETDELIM); /* Could remove for non-packed by dup ENDSEQ. */
+ } else {
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ putchecktag(c, f, wire_type, LABEL_DISPATCH);
+ dispatchtarget(c, method, f, wire_type);
+ putop(c, parse_type, sel);
+ }
+}
+
+/* Adds bytecode for parsing the given message to the given decoderplan,
+ * while adding all dispatch targets to this message's dispatch table. */
+static void compile_method(compiler *c, upb_pbdecodermethod *method) {
+ const upb_handlers *h;
+ const upb_msgdef *md;
+ uint32_t* start_pc;
+ upb_msg_field_iter i;
+ upb_value val;
+
+ UPB_ASSERT(method);
+
+ /* Clear all entries in the dispatch table. */
+ upb_inttable_uninit(&method->dispatch);
+ upb_inttable_init(&method->dispatch, UPB_CTYPE_UINT64);
+
+ h = upb_pbdecodermethod_desthandlers(method);
+ md = upb_handlers_msgdef(h);
+
+ method->code_base.ofs = pcofs(c);
+ putop(c, OP_SETDISPATCH, &method->dispatch);
+ putsel(c, OP_STARTMSG, UPB_STARTMSG_SELECTOR, h);
+ label(c, LABEL_FIELD);
+ start_pc = c->pc;
+ for(upb_msg_field_begin(&i, md);
+ !upb_msg_field_done(&i);
+ upb_msg_field_next(&i)) {
+ const upb_fielddef *f = upb_msg_iter_field(&i);
+ upb_fieldtype_t type = upb_fielddef_type(f);
+
+ if (type == UPB_TYPE_MESSAGE && !(haslazyhandlers(h, f) && c->lazy)) {
+ generate_msgfield(c, f, method);
+ } else if (type == UPB_TYPE_STRING || type == UPB_TYPE_BYTES ||
+ type == UPB_TYPE_MESSAGE) {
+ generate_delimfield(c, f, method);
+ } else {
+ generate_primitivefield(c, f, method);
+ }
+ }
+
+ /* If there were no fields, or if no handlers were defined, we need to
+ * generate a non-empty loop body so that we can at least dispatch for unknown
+ * fields and check for the end of the message. */
+ if (c->pc == start_pc) {
+ /* Check for end-of-message. */
+ putop(c, OP_CHECKDELIM, LABEL_ENDMSG);
+ /* Unconditionally dispatch. */
+ putop(c, OP_DISPATCH, 0);
+ }
+
+ /* For now we just loop back to the last field of the message (or if none,
+ * the DISPATCH opcode for the message). */
+ putop(c, OP_BRANCH, -LABEL_FIELD);
+
+ /* Insert both a label and a dispatch table entry for this end-of-msg. */
+ label(c, LABEL_ENDMSG);
+ val = upb_value_uint64(pcofs(c) - method->code_base.ofs);
+ upb_inttable_insert(&method->dispatch, DISPATCH_ENDMSG, val);
+
+ putsel(c, OP_ENDMSG, UPB_ENDMSG_SELECTOR, h);
+ putop(c, OP_RET);
+
+ upb_inttable_compact(&method->dispatch);
+}
+
+/* Populate "methods" with new upb_pbdecodermethod objects reachable from "h".
+ * Returns the method for these handlers.
+ *
+ * Generates a new method for every destination handlers reachable from "h". */
+static void find_methods(compiler *c, const upb_handlers *h) {
+ upb_value v;
+ upb_msg_field_iter i;
+ const upb_msgdef *md;
+ upb_pbdecodermethod *method;
+
+ if (upb_inttable_lookupptr(&c->group->methods, h, &v))
+ return;
+
+ method = newmethod(h, c->group);
+ upb_inttable_insertptr(&c->group->methods, h, upb_value_ptr(method));
+
+ /* Find submethods. */
+ md = upb_handlers_msgdef(h);
+ for(upb_msg_field_begin(&i, md);
+ !upb_msg_field_done(&i);
+ upb_msg_field_next(&i)) {
+ const upb_fielddef *f = upb_msg_iter_field(&i);
+ const upb_handlers *sub_h;
+ if (upb_fielddef_type(f) == UPB_TYPE_MESSAGE &&
+ (sub_h = upb_handlers_getsubhandlers(h, f)) != NULL) {
+ /* We only generate a decoder method for submessages with handlers.
+ * Others will be parsed as unknown fields. */
+ find_methods(c, sub_h);
+ }
+ }
+}
+
+/* (Re-)compile bytecode for all messages in "msgs."
+ * Overwrites any existing bytecode in "c". */
+static void compile_methods(compiler *c) {
+ upb_inttable_iter i;
+
+ /* Start over at the beginning of the bytecode. */
+ c->pc = c->group->bytecode;
+
+ upb_inttable_begin(&i, &c->group->methods);
+ for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
+ upb_pbdecodermethod *method = upb_value_getptr(upb_inttable_iter_value(&i));
+ compile_method(c, method);
+ }
+}
+
+static void set_bytecode_handlers(mgroup *g) {
+ upb_inttable_iter i;
+ upb_inttable_begin(&i, &g->methods);
+ for(; !upb_inttable_done(&i); upb_inttable_next(&i)) {
+ upb_pbdecodermethod *m = upb_value_getptr(upb_inttable_iter_value(&i));
+ upb_byteshandler *h = &m->input_handler_;
+
+ m->code_base.ptr = g->bytecode + m->code_base.ofs;
+
+ upb_byteshandler_setstartstr(h, upb_pbdecoder_startbc, m->code_base.ptr);
+ upb_byteshandler_setstring(h, upb_pbdecoder_decode, g);
+ upb_byteshandler_setendstr(h, upb_pbdecoder_end, m);
+ }
+}
+
+
+/* TODO(haberman): allow this to be constructed for an arbitrary set of dest
+ * handlers and other mgroups (but verify we have a transitive closure). */
+const mgroup *mgroup_new(const upb_handlers *dest, bool allowjit, bool lazy) {
+ mgroup *g;
+ compiler *c;
+
+ UPB_UNUSED(allowjit);
+
+ g = newgroup();
+ c = newcompiler(g, lazy);
+ find_methods(c, dest);
+
+ /* We compile in two passes:
+ * 1. all messages are assigned relative offsets from the beginning of the
+ * bytecode (saved in method->code_base).
+ * 2. forwards OP_CALL instructions can be correctly linked since message
+ * offsets have been previously assigned.
+ *
+ * Could avoid the second pass by linking OP_CALL instructions somehow. */
+ compile_methods(c);
+ compile_methods(c);
+ g->bytecode_end = c->pc;
+ freecompiler(c);
+
+#ifdef UPB_DUMP_BYTECODE
+ {
+ FILE *f = fopen("/tmp/upb-bytecode", "w");
+ UPB_ASSERT(f);
+ dumpbc(g->bytecode, g->bytecode_end, stderr);
+ dumpbc(g->bytecode, g->bytecode_end, f);
+ fclose(f);
+
+ f = fopen("/tmp/upb-bytecode.bin", "wb");
+ UPB_ASSERT(f);
+ fwrite(g->bytecode, 1, g->bytecode_end - g->bytecode, f);
+ fclose(f);
+ }
+#endif
+
+ set_bytecode_handlers(g);
+ return g;
+}
+
+
+/* upb_pbcodecache ************************************************************/
+
+upb_pbcodecache *upb_pbcodecache_new(upb_handlercache *dest) {
+ upb_pbcodecache *c = upb_gmalloc(sizeof(*c));
+
+ if (!c) return NULL;
+
+ c->dest = dest;
+ c->allow_jit = true;
+ c->lazy = false;
+
+ c->arena = upb_arena_new();
+ if (!upb_inttable_init(&c->groups, UPB_CTYPE_CONSTPTR)) return NULL;
+
+ return c;
+}
+
+void upb_pbcodecache_free(upb_pbcodecache *c) {
+ size_t i;
+
+ for (i = 0; i < upb_inttable_count(&c->groups); i++) {
+ upb_value v;
+ bool ok = upb_inttable_lookup(&c->groups, i, &v);
+ UPB_ASSERT(ok);
+ freegroup((void*)upb_value_getconstptr(v));
+ }
+
+ upb_inttable_uninit(&c->groups);
+ upb_arena_free(c->arena);
+ upb_gfree(c);
+}
+
+bool upb_pbcodecache_allowjit(const upb_pbcodecache *c) {
+ return c->allow_jit;
+}
+
+void upb_pbcodecache_setallowjit(upb_pbcodecache *c, bool allow) {
+ UPB_ASSERT(upb_inttable_count(&c->groups) == 0);
+ c->allow_jit = allow;
+}
+
+void upb_pbdecodermethodopts_setlazy(upb_pbcodecache *c, bool lazy) {
+ UPB_ASSERT(upb_inttable_count(&c->groups) == 0);
+ c->lazy = lazy;
+}
+
+const upb_pbdecodermethod *upb_pbcodecache_get(upb_pbcodecache *c,
+ const upb_msgdef *md) {
+ upb_value v;
+ bool ok;
+ const upb_handlers *h;
+ const mgroup *g;
+
+ /* Right now we build a new DecoderMethod every time.
+ * TODO(haberman): properly cache methods by their true key. */
+ h = upb_handlercache_get(c->dest, md);
+ g = mgroup_new(h, c->allow_jit, c->lazy);
+ upb_inttable_push(&c->groups, upb_value_constptr(g));
+
+ ok = upb_inttable_lookupptr(&g->methods, h, &v);
+ UPB_ASSERT(ok);
+ return upb_value_getptr(v);
+}
git://repos.xcallymotion.com / motion2.git / blobdiff