[mips] Change kSpeculationPoisonRegister from a7 to t3

When kSpeculationPoisonRegister is a7, the test
TestFastJSWasmCall_MultipleArgs failed.

Besides, delete an unuse member named table_entry_size_.

Change-Id: Ic2c8b68d50c02dca7c41520ceb217fec33fe8cc4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2644539Reviewed-by: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Commit-Queue: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Auto-Submit: Liu yu <liuyu@loongson.cn>
Cr-Commit-Position: refs/heads/master@{#72245}

src/codegen/mips64/register-mips64.h

@@ -368,7 +368,7 @@ constexpr Register kReturnRegister2 = a0;
 constexpr Register kJSFunctionRegister = a1;
 constexpr Register kContextRegister = s7;
 constexpr Register kAllocateSizeRegister = a0;
-constexpr Register kSpeculationPoisonRegister = a7;
+constexpr Register kSpeculationPoisonRegister = t3;
 constexpr Register kInterpreterAccumulatorRegister = v0;
 constexpr Register kInterpreterBytecodeOffsetRegister = t0;
 constexpr Register kInterpreterBytecodeArrayRegister = t1;

src/deoptimizer/mips/deoptimizer-mips.cc

@@ -17,13 +17,6 @@ const int Deoptimizer::kEagerWithResumeImmedArgs1PcOffset = 2 * kInstrSize;
 const int Deoptimizer::kEagerWithResumeImmedArgs2PcOffset =
     2 * kInstrSize + kSystemPointerSize;
 
-// Maximum size of a table entry generated below.
-#ifdef _MIPS_ARCH_MIPS32R6
-const int Deoptimizer::table_entry_size_ = 2 * kInstrSize;
-#else
-const int Deoptimizer::table_entry_size_ = 3 * kInstrSize;
-#endif
-
 Float32 RegisterValues::GetFloatRegister(unsigned n) const {
   return Float32::FromBits(
       static_cast<uint32_t>(double_registers_[n].get_bits()));

src/deoptimizer/mips64/deoptimizer-mips64.cc

@@ -17,13 +17,6 @@ const int Deoptimizer::kEagerWithResumeImmedArgs1PcOffset = 2 * kInstrSize;
 const int Deoptimizer::kEagerWithResumeImmedArgs2PcOffset =
     2 * kInstrSize + kSystemPointerSize;
 
-// Maximum size of a table entry generated below.
-#ifdef _MIPS_ARCH_MIPS64R6
-const int Deoptimizer::table_entry_size_ = 2 * kInstrSize;
-#else
-const int Deoptimizer::table_entry_size_ = 3 * kInstrSize;
-#endif
-
 Float32 RegisterValues::GetFloatRegister(unsigned n) const {
   return Float32::FromBits(
       static_cast<uint32_t>(double_registers_[n].get_bits()));