Add support for near labels....

src/x64/assembler-x64.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 400 matching lines @@
   }
   L->bind_to(pos);
 }
 
 
 void Assembler::bind(Label* L) {
   bind_to(L, pc_offset());
 }
 
 
+void Assembler::bind(NearLabel* L) {
+  ASSERT(!L->is_bound());
+  last_pc_ = NULL;
+  while (L->unresolved_branches_ > 0) {
+    int branch_pos = L->unresolved_positions_[L->unresolved_branches_ - 1];
+    int disp = pc_offset() - branch_pos;
+    ASSERT(is_int8(disp));
+    set_byte_at(branch_pos - sizeof(int8_t), disp);
+    L->unresolved_branches_--;
+  }
+  L->bind_to(pc_offset());
+}
+
+
 void Assembler::GrowBuffer() {
   ASSERT(buffer_overflow());
   if (!own_buffer_) FATAL("external code buffer is too small");
 
   // Compute new buffer size.
   CodeDesc desc;  // the new buffer
   if (buffer_size_ < 4*KB) {
     desc.buffer_size = 4*KB;
   } else {
     desc.buffer_size = 2*buffer_size_;
@@ skipping 789 matching lines @@
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   ASSERT(is_uint4(cc));
   // 0000 1111 1000 tttn #32-bit disp.
   emit(0x0F);
   emit(0x80 | cc);
   emit_code_target(target, rmode);
 }
 
 
+void Assembler::j(Condition cc, NearLabel* L, Hint hint) {
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  ASSERT(0 <= cc && cc < 16);
+  if (FLAG_emit_branch_hints && hint != no_hint) emit(hint);
+  if (L->is_bound()) {
+    const int short_size = 2;
+    int offs = L->pos() - pc_offset();
+    ASSERT(offs <= 0);
+    ASSERT(is_int8(offs - short_size));
+    // 0111 tttn #8-bit disp
+    emit(0x70 | cc);
+    emit((offs - short_size) & 0xFF);
+  } else {
+    emit(0x70 | cc);
+    emit(0x00);      // The displacement will be resolved later.
+    L->link_to(pc_offset());
+  }
+}
+
+
 void Assembler::jmp(Label* L) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   const int short_size = sizeof(int8_t);
   const int long_size = sizeof(int32_t);
   if (L->is_bound()) {
     int offs = L->pos() - pc_offset() - 1;
     ASSERT(offs <= 0);
     if (is_int8(offs - short_size)) {
       // 1110 1011 #8-bit disp.
@@ skipping 22 matching lines @@
 
 void Assembler::jmp(Handle<Code> target, RelocInfo::Mode rmode) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   // 1110 1001 #32-bit disp.
   emit(0xE9);
   emit_code_target(target, rmode);
 }
 
 
+void Assembler::jmp(NearLabel* L) {
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  if (L->is_bound()) {
+    const int short_size = sizeof(int8_t);
+    int offs = L->pos() - pc_offset();
+    ASSERT(offs <= 0);
+    ASSERT(is_int8(offs - short_size));
+    // 1110 1011 #8-bit disp.
+    emit(0xEB);
+    emit((offs - short_size) & 0xFF);
+  } else {
+    emit(0xEB);
+    emit(0x00);      // The displacement will be resolved later.
+    L->link_to(pc_offset());
+  }
+}
+
+
 void Assembler::jmp(Register target) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   // Opcode FF/4 r64.
   emit_optional_rex_32(target);
   emit(0xFF);
   emit_modrm(0x4, target);
 }
 
 
@@ skipping 1668 matching lines @@
   // specially coded on x64 means that it is a relative 32 bit address, as used
   // by branch instructions.
   return (1 << rmode_) & kApplyMask;
 }
 
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64