PPC/s390: [regexp] Port RegExpExecStub to CSA (mostly)

src/ppc/code-stubs-ppc.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_PPC
 
 #include "src/code-stubs.h"
 #include "src/api-arguments.h"
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 1227 matching lines @@
   // Argument 8 (r10): Indicate that this is a direct call from JavaScript.
   __ li(r10, Operand(1));
 
   // Argument 7 (r9): Start (high end) of backtracking stack memory area.
   ExternalReference address_of_regexp_stack_memory_address =
       ExternalReference::address_of_regexp_stack_memory_address(isolate());
   ExternalReference address_of_regexp_stack_memory_size =
       ExternalReference::address_of_regexp_stack_memory_size(isolate());
   __ mov(r11, Operand(address_of_regexp_stack_memory_address));
   __ LoadP(r11, MemOperand(r11, 0));
-  __ mov(r12, Operand(address_of_regexp_stack_memory_size));
-  __ LoadP(r12, MemOperand(r12, 0));
-  __ add(r9, r11, r12);
+  __ mov(ip, Operand(address_of_regexp_stack_memory_size));

[jgruber, 2017/03/17 07:15:49]

Out of curiosity, is ip not the instruction pointer? If it is, why can we
overwrite it?

[john.yan, 2017/03/17 13:48:41]

ip on ppc/s390 is the Inter Procedural register.

+  __ LoadP(ip, MemOperand(ip, 0));
+  __ add(r9, r11, ip);
 
   // Argument 6 (r8): Set the number of capture registers to zero to force
   // global egexps to behave as non-global.  This does not affect non-global
   // regexps.
   __ li(r8, Operand::Zero());
 
   // Argument 5 (r7): static offsets vector buffer.
   __ mov(
       r7,
       Operand(ExternalReference::address_of_static_offsets_vector(isolate())));
@@ skipping 1915 matching lines @@
       fp, (PropertyCallbackArguments::kReturnValueOffset + 3) * kPointerSize);
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref,
                            kStackUnwindSpace, NULL, return_value_operand, NULL);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_PPC