Add new relocation type WASM_MEMORY_SIZE_REFERENCE, use relocatable pointers to update wasm memory …

src/ia32/assembler-ia32.cc

Index: src/ia32/assembler-ia32.cc
diff --git a/src/ia32/assembler-ia32.cc b/src/ia32/assembler-ia32.cc
index fac2d66bcdfea30db13eb66d1cbffe840c7199c9..e6f1d83cb59c2d1a15fb69ceb0ffabfd430547dc 100644
--- a/src/ia32/assembler-ia32.cc
+++ b/src/ia32/assembler-ia32.cc
@@ -186,6 +186,42 @@ 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