MIPS: Fixing illegal use of at register

src/compiler/mips/code-generator-mips.cc

Index: src/compiler/mips/code-generator-mips.cc
diff --git a/src/compiler/mips/code-generator-mips.cc b/src/compiler/mips/code-generator-mips.cc
index 7d9f204c6443ffe27f20c5b30cdd58be831f76f7..7769b9e739ec5873e47b32a0e9060082e7350e5e 100644
--- a/src/compiler/mips/code-generator-mips.cc
+++ b/src/compiler/mips/code-generator-mips.cc
@@ -304,8 +304,8 @@ FPUCondition FlagsConditionToConditionCmpFPU(bool& predicate,
     if (instr->InputAt(0)->IsRegister()) {                                    \
       auto offset = i.InputRegister(0);                                       \
       __ Branch(USE_DELAY_SLOT, ool->entry(), hs, offset, i.InputOperand(1)); \
-      __ addu(at, i.InputRegister(2), offset);                                \
-      __ asm_instr(result, MemOperand(at, 0));                                \
+      __ addu(kScratchReg, i.InputRegister(2), offset);                       \
+      __ asm_instr(result, MemOperand(kScratchReg, 0));                       \
     } else {                                                                  \
       auto offset = i.InputOperand(0).immediate();                            \
       __ Branch(ool->entry(), ls, i.InputRegister(1), Operand(offset));       \
@@ -322,8 +322,8 @@ FPUCondition FlagsConditionToConditionCmpFPU(bool& predicate,
     if (instr->InputAt(0)->IsRegister()) {                                    \
       auto offset = i.InputRegister(0);                                       \
       __ Branch(USE_DELAY_SLOT, ool->entry(), hs, offset, i.InputOperand(1)); \
-      __ addu(at, i.InputRegister(2), offset);                                \
-      __ asm_instr(result, MemOperand(at, 0));                                \
+      __ addu(kScratchReg, i.InputRegister(2), offset);                       \
+      __ asm_instr(result, MemOperand(kScratchReg, 0));                       \
     } else {                                                                  \
       auto offset = i.InputOperand(0).immediate();                            \
       __ Branch(ool->entry(), ls, i.InputRegister(1), Operand(offset));       \
@@ -340,8 +340,8 @@ FPUCondition FlagsConditionToConditionCmpFPU(bool& predicate,
       auto offset = i.InputRegister(0);                                \
       auto value = i.Input##width##Register(2);                        \
       __ Branch(USE_DELAY_SLOT, &done, hs, offset, i.InputOperand(1)); \
-      __ addu(at, i.InputRegister(3), offset);                         \
-      __ asm_instr(value, MemOperand(at, 0));                          \
+      __ addu(kScratchReg, i.InputRegister(3), offset);                \
+      __ asm_instr(value, MemOperand(kScratchReg, 0));                 \
     } else {                                                           \
       auto offset = i.InputOperand(0).immediate();                     \
       auto value = i.Input##width##Register(2);                        \
@@ -359,8 +359,8 @@ FPUCondition FlagsConditionToConditionCmpFPU(bool& predicate,
       auto offset = i.InputRegister(0);                                \
       auto value = i.InputRegister(2);                                 \
       __ Branch(USE_DELAY_SLOT, &done, hs, offset, i.InputOperand(1)); \
-      __ addu(at, i.InputRegister(3), offset);                         \
-      __ asm_instr(value, MemOperand(at, 0));                          \
+      __ addu(kScratchReg, i.InputRegister(3), offset);                \
+      __ asm_instr(value, MemOperand(kScratchReg, 0));                 \
     } else {                                                           \
       auto offset = i.InputOperand(0).immediate();                     \
       auto value = i.InputRegister(2);                                 \