ARM: Implement PatchStackCheckCodeAt and RevertStackCheckCode.

src/deoptimizer.cc

 // Copyright 2010 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 802 matching lines @@
 void Deoptimizer::PatchStackCheckCode(Code* unoptimized_code,
                                       Code* check_code,
                                       Code* replacement_code) {
   // Iterate over the stack check table and patch every stack check
   // call to an unconditional call to the replacement code.
   ASSERT(unoptimized_code->kind() == Code::FUNCTION);
   Address stack_check_cursor = unoptimized_code->instruction_start() +
       unoptimized_code->stack_check_table_offset();
   uint32_t table_length = Memory::uint32_at(stack_check_cursor);
   stack_check_cursor += kIntSize;
+  Address first_site = 0;
+  Address last_site = 0;
   for (uint32_t i = 0; i < table_length; ++i) {
     uint32_t pc_offset = Memory::uint32_at(stack_check_cursor + kIntSize);
     Address pc_after = unoptimized_code->instruction_start() + pc_offset;
     PatchStackCheckCodeAt(pc_after, check_code, replacement_code);
     stack_check_cursor += 2 * kIntSize;
+    if (first_site == 0) {
+      first_site = pc_after;
+    }
+    last_site = pc_after;
+  }
+  if (table_length > 0) {
+    // Flush instruction cache for the patched code blocks.
+    uint32_t length = last_site - first_site + patch_size();

[Søren Thygesen Gjesse, 2011/02/04 13:54:27]

If you use the CodePatcher the i-cache flushing is automatic.

[Karl Klose, 2011/02/04 18:06:49]

Done. I used the code patcher and removed the flushing here.

+    CPU::FlushICache(first_site - patch_size(), length);
   }
 }
 
 
 void Deoptimizer::RevertStackCheckCode(Code* unoptimized_code,
                                        Code* check_code,
                                        Code* replacement_code) {
   // Iterate over the stack check table and revert the patched
   // stack check calls.
   ASSERT(unoptimized_code->kind() == Code::FUNCTION);
   Address stack_check_cursor = unoptimized_code->instruction_start() +
       unoptimized_code->stack_check_table_offset();
   uint32_t table_length = Memory::uint32_at(stack_check_cursor);
   stack_check_cursor += kIntSize;
+  Address first_site = 0;
+  Address last_site = 0;
   for (uint32_t i = 0; i < table_length; ++i) {
     uint32_t pc_offset = Memory::uint32_at(stack_check_cursor + kIntSize);
     Address pc_after = unoptimized_code->instruction_start() + pc_offset;
     RevertStackCheckCodeAt(pc_after, check_code, replacement_code);
     stack_check_cursor += 2 * kIntSize;
+    if (first_site == 0) {
+      first_site = pc_after;
+    }
+    last_site = pc_after;
+  }
+  if (table_length > 0) {
+    // Flush instruction cache for the patched code blocks.
+    uint32_t length = last_site - first_site + patch_size();

[Søren Thygesen Gjesse, 2011/02/04 13:54:27]

Ditto.

[Karl Klose, 2011/02/04 18:06:49]

Done. I used the code patcher and removed the flushing here.

+    CPU::FlushICache(first_site - patch_size(), length);
   }
 }
 
 
 unsigned Deoptimizer::ComputeInputFrameSize() const {
   unsigned fixed_size = ComputeFixedSize(function_);
   // The fp-to-sp delta already takes the context and the function
   // into account so we have to avoid double counting them (-2).
   unsigned result = fixed_size + fp_to_sp_delta_ - (2 * kPointerSize);
 #ifdef DEBUG
@@ skipping 319 matching lines @@
                           Deoptimizer::HandleWeakDeoptimizedCode);
 }
 
 
 DeoptimizingCodeListNode::~DeoptimizingCodeListNode() {
   GlobalHandles::Destroy(reinterpret_cast<Object**>(code_.location()));
 }
 
 
 } }  // namespace v8::internal