MIPS: Remove unsafe EmitLoadRegister usage in AddI/SubI for constant right operand.

src/mips/macro-assembler-mips.cc

Index: src/mips/macro-assembler-mips.cc
diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc
index 8b6c4a44970ce54e7228deeb405d94bcc1c4ebe1..190af3b8768e87831e0e7fbf12c96e3d860b382f 100644
--- a/src/mips/macro-assembler-mips.cc
+++ b/src/mips/macro-assembler-mips.cc
@@ -4452,17 +4452,17 @@ void MacroAssembler::AdduAndCheckForOverflow(Register dst, Register left,
   } else {
     if (dst.is(left)) {
       mov(scratch, left);                   // Preserve left.
-      addiu(dst, left, right.immediate());  // Left is overwritten.
+      Addu(dst, left, right.immediate());   // Left is overwritten.
       xor_(scratch, dst, scratch);          // Original left.
       // Load right since xori takes uint16 as immediate.
-      addiu(t9, zero_reg, right.immediate());
+      Addu(t9, zero_reg, right);
       xor_(overflow_dst, dst, t9);
       and_(overflow_dst, overflow_dst, scratch);
     } else {
       addiu(dst, left, right.immediate());
       xor_(overflow_dst, dst, left);
       // Load right since xori takes uint16 as immediate.
-      addiu(t9, zero_reg, right.immediate());
+      Addu(t9, zero_reg, right);
       xor_(scratch, dst, t9);
       and_(overflow_dst, scratch, overflow_dst);
     }
@@ -4520,17 +4520,17 @@ void MacroAssembler::SubuAndCheckForOverflow(Register dst, Register left,
   } else {
     if (dst.is(left)) {
       mov(scratch, left);                      // Preserve left.
-      addiu(dst, left, -(right.immediate()));  // Left is overwritten.
+      Subu(dst, left, right);                  // Left is overwritten.
       xor_(overflow_dst, dst, scratch);        // scratch is original left.
       // Load right since xori takes uint16 as immediate.
-      addiu(t9, zero_reg, right.immediate());
+      Addu(t9, zero_reg, right);
       xor_(scratch, scratch, t9);  // scratch is original left.
       and_(overflow_dst, scratch, overflow_dst);
     } else {
-      addiu(dst, left, -(right.immediate()));
+      Subu(dst, left, right);
       xor_(overflow_dst, dst, left);
       // Load right since xori takes uint16 as immediate.
-      addiu(t9, zero_reg, right.immediate());
+      Addu(t9, zero_reg, right);
       xor_(scratch, left, t9);
       and_(overflow_dst, scratch, overflow_dst);
     }