Add support for near labels....

src/ia32/assembler-ia32.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 1493 matching lines @@
       // Relative address, relative to point after address.
       int imm32 = pos - (fixup_pos + sizeof(int32_t));
       long_at_put(fixup_pos, imm32);
     }
     disp.next(L);
   }
   L->bind_to(pos);
 }
 
 
-void Assembler::link_to(Label* L, Label* appendix) {
-  EnsureSpace ensure_space(this);
-  last_pc_ = NULL;
-  if (appendix->is_linked()) {
-    if (L->is_linked()) {
-      // Append appendix to L's list.
-      Label p;
-      Label q = *L;
-      do {
-        p = q;
-        Displacement disp = disp_at(&q);
-        disp.next(&q);
-      } while (q.is_linked());
-      Displacement disp = disp_at(&p);
-      disp.link_to(appendix);
-      disp_at_put(&p, disp);
-      p.Unuse();  // to avoid assertion failure in ~Label
-    } else {
-      // L is empty, simply use appendix.
-      *L = *appendix;
-    }
-  }
-  appendix->Unuse();  // appendix should not be used anymore
-}
-
-
 void Assembler::bind(Label* L) {
   EnsureSpace ensure_space(this);
   last_pc_ = NULL;
   ASSERT(!L->is_bound());  // label can only be bound once
   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::call(Label* L) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   if (L->is_bound()) {
     const int long_size = 5;
     int offs = L->pos() - pc_offset();
     ASSERT(offs <= 0);
     // 1110 1000 #32-bit disp.
     EMIT(0xE8);
     emit(offs - long_size);
@@ skipping 76 matching lines @@
 
 void Assembler::jmp(Handle<Code> code, RelocInfo::Mode rmode) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   ASSERT(RelocInfo::IsCodeTarget(rmode));
   EMIT(0xE9);
   emit(reinterpret_cast<intptr_t>(code.location()), rmode);
 }
 
 
+void Assembler::jmp(NearLabel* L) {
+  EnsureSpace ensure_space(this);
+  last_pc_ = pc_;
+  if (L->is_bound()) {
+    const int short_size = 2;
+    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::j(Condition cc, Label* 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;
     const int long_size  = 6;
     int offs = L->pos() - pc_offset();
@@ skipping 35 matching lines @@
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   if (FLAG_emit_branch_hints && hint != no_hint) EMIT(hint);
   // 0000 1111 1000 tttn #32-bit disp
   EMIT(0x0F);
   EMIT(0x80 | cc);
   emit(reinterpret_cast<intptr_t>(code.location()), RelocInfo::CODE_TARGET);
 }
 
 
+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());
+  }
+}
+
+
 // FPU instructions.
 
 void Assembler::fld(int i) {
   EnsureSpace ensure_space(this);
   last_pc_ = pc_;
   emit_farith(0xD9, 0xC0, i);
 }
 
 
 void Assembler::fstp(int i) {
@@ skipping 903 matching lines @@
     fprintf(coverage_log, "%s\n", file_line);
     fflush(coverage_log);
   }
 }
 
 #endif
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32