X87: Add new relocation type WASM_MEMORY_SIZE_REFERENCE, use relocatable pointers to update wasm me…

src/x87/assembler-x87.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 83 matching lines @@
   // branch instructions.  These are also the ones that need changing when a
   // code object moves.
   return (1 << rmode_) & kApplyMask;
 }
 
 
 bool RelocInfo::IsInConstantPool() {
   return false;
 }
 
+Address RelocInfo::wasm_memory_reference() {
+  DCHECK(IsWasmMemoryReference(rmode_));
+  return Memory::Address_at(pc_);
+}
+
+uint32_t RelocInfo::wasm_memory_size_reference() {
+  DCHECK(IsWasmMemorySizeReference(rmode_));
+  return Memory::uint32_at(pc_);
+}
+
+void RelocInfo::update_wasm_memory_reference(
+    Address old_base, Address new_base, uint32_t old_size, uint32_t new_size,
+    ICacheFlushMode icache_flush_mode) {
+  DCHECK(IsWasmMemoryReference(rmode_) || IsWasmMemorySizeReference(rmode_));
+  if (IsWasmMemoryReference(rmode_)) {
+    Address updated_reference;
+    DCHECK(old_base <= wasm_memory_reference() &&
+           wasm_memory_reference() < old_base + old_size);
+    updated_reference = new_base + (wasm_memory_reference() - old_base);
+    DCHECK(new_base <= updated_reference &&
+           updated_reference < new_base + new_size);
+    Memory::Address_at(pc_) = updated_reference;
+  } else if (IsWasmMemorySizeReference(rmode_)) {
+    uint32_t updated_size_reference;
+    DCHECK(wasm_memory_size_reference() <= old_size);
+    updated_size_reference =
+        new_size + (wasm_memory_size_reference() - old_size);
+    DCHECK(updated_size_reference <= new_size);
+    Memory::uint32_at(pc_) = updated_size_reference;
+  } else {
+    UNREACHABLE();
+  }
+  if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
+    Assembler::FlushICache(isolate_, pc_, sizeof(int32_t));
+  }
+}
 
 // -----------------------------------------------------------------------------
 // Implementation of Operand
 
 Operand::Operand(Register base, int32_t disp, RelocInfo::Mode rmode) {
   // [base + disp/r]
   if (disp == 0 && RelocInfo::IsNone(rmode) && !base.is(ebp)) {
     // [base]
     set_modrm(0, base);
     if (base.is(esp)) set_sib(times_1, esp, base);
@@ skipping 2070 matching lines @@
     fflush(coverage_log);
   }
 }
 
 #endif
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87