Emulate MLS on pre-ARMv6T2. Cleaned up thumbee vs. thumb2 confusion.

src/arm/assembler-arm.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 66 matching lines @@
 
   // Only use statically determined features for cross compile (snapshot).
   if (cross_compile) return;
 
 #ifndef __arm__
   // For the simulator build, use whatever the flags specify.
   if (FLAG_enable_armv7) {
     supported_ |= 1u << ARMv7;
     if (FLAG_enable_vfp3) supported_ |= 1u << VFP3;
     if (FLAG_enable_neon) supported_ |= 1u << NEON | 1u << VFP32DREGS;
-    if (FLAG_enable_sudiv)  supported_ |= 1u << SUDIV;
+    if (FLAG_enable_sudiv) supported_ |= 1u << SUDIV;
     if (FLAG_enable_movw_movt) supported_ |= 1u << MOVW_MOVT_IMMEDIATE_LOADS;
     if (FLAG_enable_32dregs) supported_ |= 1u << VFP32DREGS;
   }
+  if (FLAG_enable_mls) supported_ |= 1u << MLS;
   if (FLAG_enable_unaligned_accesses) supported_ |= 1u << UNALIGNED_ACCESSES;
 
 #else  // __arm__
   // Probe for additional features at runtime.
   CPU cpu;
   if (FLAG_enable_vfp3 && cpu.has_vfp3()) {
     // This implementation also sets the VFP flags if runtime
     // detection of VFP returns true. VFPv3 implies ARMv7, see ARM DDI
     // 0406B, page A1-6.
     supported_ |= 1u << VFP3 | 1u << ARMv7;
   }
 
   if (FLAG_enable_neon && cpu.has_neon()) supported_ |= 1u << NEON;
   if (FLAG_enable_sudiv && cpu.has_idiva()) supported_ |= 1u << SUDIV;
+  if (FLAG_enable_mls && cpu.has_thumbee()) supported_ |= 1u << MLS;

[Rodolph Perfetta, 2014/06/13 10:13:23]

DBC: You should check for ARMv7 not ThumbEE.

ThumbEE is deprecated, the newer cores (A53, A57) don't have it.

 
   if (cpu.architecture() >= 7) {
     if (FLAG_enable_armv7) supported_ |= 1u << ARMv7;
     if (FLAG_enable_unaligned_accesses) supported_ |= 1u << UNALIGNED_ACCESSES;
     // Use movw/movt for QUALCOMM ARMv7 cores.
     if (FLAG_enable_movw_movt && cpu.implementer() == CPU::QUALCOMM) {
       supported_ |= 1u << MOVW_MOVT_IMMEDIATE_LOADS;
     }
   }
 
@@ skipping 622 matching lines @@
 // instruction using the label.
 //
 // The linked labels form a link chain by making the branch offset
 // in the instruction steam to point to the previous branch
 // instruction using the same label.
 //
 // The link chain is terminated by a branch offset pointing to the
 // same position.
 
 
-int Assembler::target_at(int pos)  {
+int Assembler::target_at(int pos) {
   Instr instr = instr_at(pos);
   if (is_uint24(instr)) {
     // Emitted link to a label, not part of a branch.
     return instr;
   }
   ASSERT((instr & 7*B25) == 5*B25);  // b, bl, or blx imm24
   int imm26 = ((instr & kImm24Mask) << 8) >> 6;
   if ((Instruction::ConditionField(instr) == kSpecialCondition) &&
       ((instr & B24) != 0)) {
     // blx uses bit 24 to encode bit 2 of imm26
@@ skipping 716 matching lines @@
                     SBit s, Condition cond) {
   ASSERT(!dst.is(pc) && !src1.is(pc) && !src2.is(pc) && !srcA.is(pc));
   emit(cond | A | s | dst.code()*B16 | srcA.code()*B12 |
        src2.code()*B8 | B7 | B4 | src1.code());
 }
 
 
 void Assembler::mls(Register dst, Register src1, Register src2, Register srcA,
                     Condition cond) {
   ASSERT(!dst.is(pc) && !src1.is(pc) && !src2.is(pc) && !srcA.is(pc));
+  ASSERT(IsEnabled(MLS));
   emit(cond | B22 | B21 | dst.code()*B16 | srcA.code()*B12 |
        src2.code()*B8 | B7 | B4 | src1.code());
 }
 
 
 void Assembler::sdiv(Register dst, Register src1, Register src2,
                      Condition cond) {
   ASSERT(!dst.is(pc) && !src1.is(pc) && !src2.is(pc));
   ASSERT(IsEnabled(SUDIV));
   emit(cond | B26 | B25| B24 | B20 | dst.code()*B16 | 0xf * B12 |
@@ skipping 2167 matching lines @@
   ASSERT((index_64bit == count_of_64bit_) &&
          (index_code_ptr == (index_64bit + count_of_code_ptr_)) &&
          (index_heap_ptr == (index_code_ptr + count_of_heap_ptr_)) &&
          (index_32bit == (index_heap_ptr + count_of_32bit_)));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM