ARM backend support for pld (preload data) instruction

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 1477 matching lines @@
     }
     instr = I | rotate_imm*B8 | immed_8;
   } else {
     ASSERT(!src.rs_.is_valid() && src.shift_imm_ == 0);  // only rm allowed
     instr = src.rm_.code();
   }
   emit(cond | instr | B24 | B21 | fields | 15*B12);
 }
 
 
+// Preload data instruction
+void Assembler::pld(const MemOperand& src) {

[Sven Panne, 2013/02/28 07:36:11]

This looks suspiciously like a specialization of addrmod2. Can't we reuse
addrmod2 here to avoid duplicating more than 20 lines?

+  Instr instr = kCondMask | B26 | B | L | kRdMask;
+  int am = src.am_;
+  ASSERT((am & (P | W)) == P);
+  if (!src.rm_.is_valid()) {
+    // Immediate offset.
+    int offset_12 = src.offset_;
+    if (offset_12 < 0) {
+      offset_12 = -offset_12;
+      am ^= U;
+    }
+    ASSERT(offset_12 >= 0);  // no masking needed
+    instr |= offset_12;
+  } else {
+    // Register offset (shift_imm_ and shift_op_ are 0) or scaled
+    // register offset the constructors make sure than both shift_imm_
+    // and shift_op_ are initialized.
+    ASSERT(!src.rm_.is(pc));
+    instr |= B25 | src.shift_imm_*B7 | src.shift_op_ | src.rm_.code();
+  }
+  emit(instr | am | src.rn_.code()*B16);
+}
+
+
 // Load/Store instructions.
 void Assembler::ldr(Register dst, const MemOperand& src, Condition cond) {
   if (dst.is(pc)) {
     positions_recorder()->WriteRecordedPositions();
   }
   addrmod2(cond | B26 | L, dst, src);
 }
 
 
 void Assembler::str(Register src, const MemOperand& dst, Condition cond) {
@@ skipping 1518 matching lines @@
 
   // Since a constant pool was just emitted, move the check offset forward by
   // the standard interval.
   next_buffer_check_ = pc_offset() + kCheckPoolInterval;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM