MIPS: Fix reg use in SIMD.js Add the other SIMD Phase 1 types.

Port 7b9670b6

Only fails in debug builds.

TEST=mjsunit/harmony/simd
BUG=

Review URL: https://codereview.chromium.org/1264103005

Cr-Commit-Position: refs/heads/master@{#29993}

src/mips/lithium-codegen-mips.cc

@@ -2186,7 +2186,7 @@ void LCodeGen::DoBranch(LBranch* instr) {
         Label not_simd;
         const Register scratch = scratch1();
         __ lbu(scratch, FieldMemOperand(map, Map::kInstanceTypeOffset));
-        __ Branch(&not_simd, lt, at, Operand(FIRST_SIMD_VALUE_TYPE));
+        __ Branch(&not_simd, lt, scratch, Operand(FIRST_SIMD_VALUE_TYPE));
         __ Branch(instr->TrueLabel(chunk_), le, scratch,
                   Operand(LAST_SIMD_VALUE_TYPE));
         __ bind(&not_simd);

src/mips64/lithium-codegen-mips64.cc

@@ -2287,7 +2287,7 @@ void LCodeGen::DoBranch(LBranch* instr) {
         Label not_simd;
         const Register scratch = scratch1();
         __ lbu(scratch, FieldMemOperand(map, Map::kInstanceTypeOffset));
-        __ Branch(&not_simd, lt, at, Operand(FIRST_SIMD_VALUE_TYPE));
+        __ Branch(&not_simd, lt, scratch, Operand(FIRST_SIMD_VALUE_TYPE));
         __ Branch(instr->TrueLabel(chunk_), le, scratch,
                   Operand(LAST_SIMD_VALUE_TYPE));
         __ bind(&not_simd);