MIPS: Use JIC/JIALC offset when possible

src/mips/assembler-mips.h

Index: src/mips/assembler-mips.h
diff --git a/src/mips/assembler-mips.h b/src/mips/assembler-mips.h
index 6403f06e57a2e9c9d75609b6c47a7da1c8587f85..e4b60c1d244676488a9b8bc11e759de3595e2e4e 100644
--- a/src/mips/assembler-mips.h
+++ b/src/mips/assembler-mips.h
@@ -439,6 +439,8 @@ class Operand BASE_EMBEDDED {
 
   Register rm() const { return rm_; }
 
+  RelocInfo::Mode rmode() const { return rmode_; }
+
  private:
   Register rm_;
   int32_t imm32_;  // Valid if rm_ == no_reg.
@@ -594,10 +596,19 @@ class Assembler : public AssemblerBase {
   inline static void deserialization_set_special_target_at(
       Isolate* isolate, Address instruction_payload, Code* code,
       Address target) {
-    set_target_address_at(
-        isolate,
-        instruction_payload - kInstructionsFor32BitConstant * kInstrSize, code,
-        target);
+    if (IsMipsArchVariant(kMips32r6)) {
+      // On R6 the address location is shifted by one instruction
+      set_target_address_at(
+          isolate,
+          instruction_payload -
+              (kInstructionsFor32BitConstant - 1) * kInstrSize,

[dusan.simicic, 2017/04/24 14:48:56]

If you changed this constant expression for R6 in all places in code, maybe it
would be better to redefine kInstructionsFor32BitConstant constant to have one
value for R6 and another for lower architectures. 

+          code, target);
+    } else {
+      set_target_address_at(
+          isolate,
+          instruction_payload - kInstructionsFor32BitConstant * kInstrSize,
+          code, target);
+    }
   }
 
   // This sets the internal reference at the pc.
@@ -628,7 +639,7 @@ class Assembler : public AssemblerBase {
   // Distance between the instruction referring to the address of the call
   // target and the return address.
 #ifdef _MIPS_ARCH_MIPS32R6
-  static constexpr int kCallTargetAddressOffset = 3 * kInstrSize;
+  static constexpr int kCallTargetAddressOffset = 2 * kInstrSize;
 #else
   static constexpr int kCallTargetAddressOffset = 4 * kInstrSize;
 #endif