Introduce ReadPositionFromRegister in x64 Regexp Macro Assembler

src/x64/regexp-macro-assembler-x64.cc

 // Copyright 2012 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 223 matching lines @@
   Drop();
   BranchOrBacktrack(no_condition, on_equal);
   __ bind(&fallthrough);
 }
 
 
 void RegExpMacroAssemblerX64::CheckNotBackReferenceIgnoreCase(
     int start_reg,
     Label* on_no_match) {
   Label fallthrough;
-  __ movq(rdx, register_location(start_reg));  // Offset of start of capture
-  __ movq(rbx, register_location(start_reg + 1));  // Offset of end of capture
+  ReadPositionFromRegister(rdx, start_reg);  // Offset of start of capture
+  ReadPositionFromRegister(rbx, start_reg + 1);  // Offset of end of capture
   __ subp(rbx, rdx);  // Length of capture.
 
   // -----------------------
   // rdx  = Start offset of capture.
   // rbx = Length of capture
 
   // If length is negative, this code will fail (it's a symptom of a partial or
   // illegal capture where start of capture after end of capture).
   // This must not happen (no back-reference can reference a capture that wasn't
   // closed before in the reg-exp, and we must not generate code that can cause
@@ skipping 127 matching lines @@
   __ bind(&fallthrough);
 }
 
 
 void RegExpMacroAssemblerX64::CheckNotBackReference(
     int start_reg,
     Label* on_no_match) {
   Label fallthrough;
 
   // Find length of back-referenced capture.
-  __ movq(rdx, register_location(start_reg));
-  __ movq(rax, register_location(start_reg + 1));
+  ReadPositionFromRegister(rdx, start_reg);  // Offset of start of capture
+  ReadPositionFromRegister(rax, start_reg + 1);  // Offset of end of capture
   __ subp(rax, rdx);  // Length to check.
 
   // Fail on partial or illegal capture (start of capture after end of capture).
   // This must not happen (no back-reference can reference a capture that wasn't
   // closed before in the reg-exp).
   __ Check(greater_equal, kInvalidCaptureReferenced);
 
   // Succeed on empty capture (including non-participating capture)
   __ j(equal, &fallthrough);
 
@@ skipping 335 matching lines @@
 
   __ bind(&stack_ok);
 
   // Allocate space on stack for registers.
   __ subp(rsp, Immediate(num_registers_ * kPointerSize));
   // Load string length.
   __ movp(rsi, Operand(rbp, kInputEnd));
   // Load input position.
   __ movp(rdi, Operand(rbp, kInputStart));
   // Set up rdi to be negative offset from string end.
-  __ subp(rdi, rsi);
+  __ subq(rdi, rsi);
   // Set rax to address of char before start of the string
   // (effectively string position -1).
   __ movp(rbx, Operand(rbp, kStartIndex));
   __ negq(rbx);
   if (mode_ == UC16) {
     __ leap(rax, Operand(rdi, rbx, times_2, -char_size()));
   } else {
     __ leap(rax, Operand(rdi, rbx, times_1, -char_size()));
   }
   // Store this value in a local variable, for use when clearing
@@ skipping 63 matching lines @@
       __ movp(rdx, Operand(rbp, kStartIndex));
       __ movp(rbx, Operand(rbp, kRegisterOutput));
       __ movp(rcx, Operand(rbp, kInputEnd));
       __ subp(rcx, Operand(rbp, kInputStart));
       if (mode_ == UC16) {
         __ leap(rcx, Operand(rcx, rdx, times_2, 0));
       } else {
         __ addp(rcx, rdx);
       }
       for (int i = 0; i < num_saved_registers_; i++) {
-        __ movq(rax, register_location(i));
+        __ movp(rax, register_location(i));
         if (i == 0 && global_with_zero_length_check()) {
           // Keep capture start in rdx for the zero-length check later.
           __ movp(rdx, rax);
         }
         __ addp(rax, rcx);  // Convert to index from start, not end.
         if (mode_ == UC16) {
           __ sarp(rax, Immediate(1));  // Convert byte index to character index.
         }
         __ movl(Operand(rbx, i * kIntSize), rax);
       }
@@ skipping 232 matching lines @@
 
 
 void RegExpMacroAssemblerX64::PushRegister(int register_index,
                                            StackCheckFlag check_stack_limit) {
   __ movp(rax, register_location(register_index));
   Push(rax);
   if (check_stack_limit) CheckStackLimit();
 }
 
 
+STATIC_ASSERT(kPointerSize == kInt64Size || kPointerSize == kInt32Size);
+
+
 void RegExpMacroAssemblerX64::ReadCurrentPositionFromRegister(int reg) {
-  __ movq(rdi, register_location(reg));
+  if (kPointerSize == kInt64Size) {
+    __ movq(rdi, register_location(reg));
+  } else {
+    // Need sign extension for x32 as rdi might be used as an index register.
+    __ movsxlq(rdi, register_location(reg));
+  }
+}
+
+
+void RegExpMacroAssemblerX64::ReadPositionFromRegister(Register dst, int reg) {
+  if (kPointerSize == kInt64Size) {
+    __ movq(dst, register_location(reg));
+  } else {
+    // Need sign extension for x32 as dst might be used as an index register.
+    __ movsxlq(dst, register_location(reg));
+  }
 }
 
 
 void RegExpMacroAssemblerX64::ReadStackPointerFromRegister(int reg) {
-  __ movq(backtrack_stackpointer(), register_location(reg));
+  __ movp(backtrack_stackpointer(), register_location(reg));
   __ addp(backtrack_stackpointer(), Operand(rbp, kStackHighEnd));
 }
 
 
 void RegExpMacroAssemblerX64::SetCurrentPositionFromEnd(int by) {
   Label after_position;
   __ cmpp(rdi, Immediate(-by * char_size()));
   __ j(greater_equal, &after_position, Label::kNear);
   __ movq(rdi, Immediate(-by * char_size()));
   // On RegExp code entry (where this operation is used), the character before
@@ skipping 335 matching lines @@
   }
 }
 
 #undef __
 
 #endif  // V8_INTERPRETED_REGEXP
 
 }}  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64