PPC/s390: [interpreter] Encode BytecodeSizes as uint8_t for better cache locality

Port 3965dcd5

Original Commit Message:

    This very slightly improves the performance of bytecode array visitors.

R=verwaest@chromium.org, joransiu@ca.ibm.com, junyan@redhat.com, midawson@redhat.com
BUG=
LOG=N

Change-Id: I7952fcacc72f4166c73885fd715950b319458209
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2656455Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#72406}

src/builtins/ppc/builtins-ppc.cc

@@ -953,7 +953,7 @@ static void AdvanceBytecodeOffsetOrReturn(MacroAssembler* masm,
   __ addi(bytecode_offset, bytecode_offset, Operand(1));
   __ lbzx(bytecode, MemOperand(bytecode_array, bytecode_offset));
   __ addi(bytecode_size_table, bytecode_size_table,
-          Operand(kIntSize * interpreter::Bytecodes::kBytecodeCount));
+          Operand(kByteSize * interpreter::Bytecodes::kBytecodeCount));
   __ b(&process_bytecode);
 
   __ bind(&extra_wide);
@@ -961,7 +961,7 @@ static void AdvanceBytecodeOffsetOrReturn(MacroAssembler* masm,
   __ addi(bytecode_offset, bytecode_offset, Operand(1));
   __ lbzx(bytecode, MemOperand(bytecode_array, bytecode_offset));
   __ addi(bytecode_size_table, bytecode_size_table,
-          Operand(2 * kIntSize * interpreter::Bytecodes::kBytecodeCount));
+          Operand(2 * kByteSize * interpreter::Bytecodes::kBytecodeCount));
 
   // Load the size of the current bytecode.
   __ bind(&process_bytecode);
@@ -987,8 +987,7 @@ static void AdvanceBytecodeOffsetOrReturn(MacroAssembler* masm,
 
   __ bind(&not_jump_loop);
   // Otherwise, load the size of the current bytecode and advance the offset.
-  __ ShiftLeftImm(scratch3, bytecode, Operand(2));
-  __ lwzx(scratch3, MemOperand(bytecode_size_table, scratch3));
+  __ lbzx(scratch3, MemOperand(bytecode_size_table, bytecode));
   __ add(bytecode_offset, bytecode_offset, scratch3);
 
   __ bind(&end);

src/builtins/s390/builtins-s390.cc

@@ -1011,7 +1011,7 @@ static void AdvanceBytecodeOffsetOrReturn(MacroAssembler* masm,
   __ AddS64(bytecode_offset, bytecode_offset, Operand(1));
   __ LoadU8(bytecode, MemOperand(bytecode_array, bytecode_offset));
   __ AddS64(bytecode_size_table, bytecode_size_table,
-            Operand(kIntSize * interpreter::Bytecodes::kBytecodeCount));
+            Operand(kByteSize * interpreter::Bytecodes::kBytecodeCount));
   __ b(&process_bytecode);
 
   __ bind(&extra_wide);
@@ -1019,7 +1019,7 @@ static void AdvanceBytecodeOffsetOrReturn(MacroAssembler* masm,
   __ AddS64(bytecode_offset, bytecode_offset, Operand(1));
   __ LoadU8(bytecode, MemOperand(bytecode_array, bytecode_offset));
   __ AddS64(bytecode_size_table, bytecode_size_table,
-            Operand(2 * kIntSize * interpreter::Bytecodes::kBytecodeCount));
+            Operand(2 * kByteSize * interpreter::Bytecodes::kBytecodeCount));
 
   // Load the size of the current bytecode.
   __ bind(&process_bytecode);
@@ -1045,8 +1045,7 @@ static void AdvanceBytecodeOffsetOrReturn(MacroAssembler* masm,
 
   __ bind(&not_jump_loop);
   // Otherwise, load the size of the current bytecode and advance the offset.
-  __ ShiftLeftU64(scratch3, bytecode, Operand(2));
-  __ LoadU32(scratch3, MemOperand(bytecode_size_table, scratch3));
+  __ LoadU8(scratch3, MemOperand(bytecode_size_table, bytecode));
   __ AddS64(bytecode_offset, bytecode_offset, scratch3);
 
   __ bind(&end);