Harmony: optimize Math.clz32.

src/ia32/disasm-ia32.cc

 // Copyright 2011 the V8 project authors. 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.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 863 matching lines @@
     case 0xA2: return "cpuid";
     case 0xBE: return "movsx_b";
     case 0xBF: return "movsx_w";
     case 0xB6: return "movzx_b";
     case 0xB7: return "movzx_w";
     case 0xAF: return "imul";
     case 0xA5: return "shld";
     case 0xAD: return "shrd";
     case 0xAC: return "shrd";  // 3-operand version.
     case 0xAB: return "bts";
+    case 0xBD: return "bsr";
     default: return NULL;
   }
 }
 
 
 // Disassembled instruction '*instr' and writes it into 'out_buffer'.
 int DisassemblerIA32::InstructionDecode(v8::internal::Vector<char> out_buffer,
                                         byte* instr) {
   tmp_buffer_pos_ = 0;  // starting to write as position 0
   byte* data = instr;
@@ skipping 195 matching lines @@
           } else if ((f0byte & 0xF0) == 0x80) {
             data += JumpConditional(data, branch_hint);
           } else if (f0byte == 0xBE || f0byte == 0xBF || f0byte == 0xB6 ||
                      f0byte == 0xB7 || f0byte == 0xAF) {
             data += 2;
             data += PrintOperands(f0mnem, REG_OPER_OP_ORDER, data);
           } else if ((f0byte & 0xF0) == 0x90) {
             data += SetCC(data);
           } else if ((f0byte & 0xF0) == 0x40) {
             data += CMov(data);
+          } else if (f0byte == 0xAB || f0byte == 0xA5 || f0byte == 0xAD) {
+            // shrd, shld, bts
+            data += 2;
+            AppendToBuffer("%s ", f0mnem);
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            data += PrintRightOperand(data);
+            if (f0byte == 0xAB) {
+              AppendToBuffer(",%s", NameOfCPURegister(regop));
+            } else {
+              AppendToBuffer(",%s,cl", NameOfCPURegister(regop));
+            }
+          } else if (f0byte == 0xBD) {
+            data += 2;
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            AppendToBuffer("%s %s,", f0mnem, NameOfCPURegister(regop));
+            data += PrintRightOperand(data);
           } else {
-            data += 2;
-            if (f0byte == 0xAB || f0byte == 0xA5 || f0byte == 0xAD) {
-              // shrd, shld, bts
-              AppendToBuffer("%s ", f0mnem);
-              int mod, regop, rm;
-              get_modrm(*data, &mod, &regop, &rm);
-              data += PrintRightOperand(data);
-              if (f0byte == 0xAB) {
-                AppendToBuffer(",%s", NameOfCPURegister(regop));
-              } else {
-                AppendToBuffer(",%s,cl", NameOfCPURegister(regop));
-              }
-            } else {
-              UnimplementedInstruction();
-            }
+            UnimplementedInstruction();
           }
         }
         break;
 
       case 0x8F:
         { data++;
           int mod, regop, rm;
           get_modrm(*data, &mod, &regop, &rm);
           if (regop == eax) {
             AppendToBuffer("pop ");
@@ skipping 474 matching lines @@
             int mod, regop, rm;
             get_modrm(*data, &mod, &regop, &rm);
             AppendToBuffer("cvttss2si %s,", NameOfCPURegister(regop));
             data += PrintRightXMMOperand(data);
           } else if (b2 == 0x5A) {
             data += 3;
             int mod, regop, rm;
             get_modrm(*data, &mod, &regop, &rm);
             AppendToBuffer("cvtss2sd %s,", NameOfXMMRegister(regop));
             data += PrintRightXMMOperand(data);
-          } else  if (b2 == 0x6F) {
+          } else if (b2 == 0x6F) {
             data += 3;
             int mod, regop, rm;
             get_modrm(*data, &mod, &regop, &rm);
             AppendToBuffer("movdqu %s,", NameOfXMMRegister(regop));
             data += PrintRightXMMOperand(data);
-          } else  if (b2 == 0x7F) {
+          } else if (b2 == 0x7F) {
             AppendToBuffer("movdqu ");
             data += 3;
             int mod, regop, rm;
             get_modrm(*data, &mod, &regop, &rm);
             data += PrintRightXMMOperand(data);
             AppendToBuffer(",%s", NameOfXMMRegister(regop));
           } else {
             UnimplementedInstruction();
           }
         } else if (*(data+1) == 0xA5) {
@@ skipping 137 matching lines @@
       fprintf(f, "  ");
     }
     fprintf(f, "  %s\n", buffer.start());
   }
 }
 
 
 }  // namespace disasm
 
 #endif  // V8_TARGET_ARCH_IA32