Implement byte swapping instructions on MIPS32 and MIPS64.

src/mips64/macro-assembler-mips64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <limits.h>  // For LONG_MIN, LONG_MAX.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
@@ skipping 11 matching lines @@
     : Assembler(arg_isolate, buffer, size),
       generating_stub_(false),
       has_frame_(false),
       has_double_zero_reg_set_(false) {
   if (create_code_object == CodeObjectRequired::kYes) {
     code_object_ =
         Handle<Object>::New(isolate()->heap()->undefined_value(), isolate());
   }
 }
 
-
 void MacroAssembler::Load(Register dst,
                           const MemOperand& src,
                           Representation r) {
   DCHECK(!r.IsDouble());
   if (r.IsInteger8()) {
     lb(dst, src);
   } else if (r.IsUInteger8()) {
     lbu(dst, src);
   } else if (r.IsInteger16()) {
     lh(dst, src);
@@ skipping 1274 matching lines @@
     Register tmp = rd.is(rt) ? scratch : rd;
     DCHECK(!tmp.is(rt));
     dsll(tmp, rs, sa);
     Daddu(rd, rt, tmp);
   }
 }
 
 
 // ------------Pseudo-instructions-------------
 
+// Change endianness
+void MacroAssembler::ByteSwapSigned(Register reg, int operand_size) {
+  DCHECK(operand_size == 1 || operand_size == 2 || operand_size == 4 ||
+         operand_size == 8);
+  DCHECK(kArchVariant == kMips64r6 || kArchVariant == kMips64r2);
+  if (operand_size == 1) {
+    seb(reg, reg);
+    sll(reg, reg, 0);
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  } else if (operand_size == 2) {
+    seh(reg, reg);
+    sll(reg, reg, 0);
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  } else if (operand_size == 4) {
+    sll(reg, reg, 0);
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  } else {
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  }
+}
+
+void MacroAssembler::ByteSwapUnsigned(Register reg, int operand_size) {
+  DCHECK(operand_size == 1 || operand_size == 2 || operand_size == 4);
+  if (operand_size == 1) {
+    andi(reg, reg, 0xFF);
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  } else if (operand_size == 2) {
+    andi(reg, reg, 0xFFFF);
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  } else {
+    dsll32(reg, reg, 0);
+    dsrl32(reg, reg, 0);
+    dsbh(reg, reg);
+    dshd(reg, reg);
+  }
+}
+
 void MacroAssembler::Ulw(Register rd, const MemOperand& rs) {
   DCHECK(!rd.is(at));
   DCHECK(!rs.rm().is(at));
   if (kArchVariant == kMips64r6) {
     lw(rd, rs);
   } else {
     DCHECK(kArchVariant == kMips64r2);
     if (is_int16(rs.offset() + kMipsLwrOffset) &&
         is_int16(rs.offset() + kMipsLwlOffset)) {
       if (!rd.is(rs.rm())) {
@@ skipping 5806 matching lines @@
   if (mag.shift > 0) sra(result, result, mag.shift);
   srl(at, dividend, 31);
   Addu(result, result, Operand(at));
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64