MIPS: Implement unaligned access instruction.

src/mips/macro-assembler-mips.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_MIPS
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
@@ skipping 1174 matching lines @@
     DCHECK(!tmp.is(rt));
     sll(tmp, rs, sa);
     Addu(rd, rt, tmp);
   }
 }
 
 
 // ------------Pseudo-instructions-------------
 
 void MacroAssembler::Ulw(Register rd, const MemOperand& rs) {
-  lwr(rd, rs);
-  lwl(rd, MemOperand(rs.rm(), rs.offset() + 3));
+  DCHECK(!rd.is(at));
+  DCHECK(!rs.rm().is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    lw(rd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    if (is_int16(rs.offset() + kMipsLwrOffset) &&
+        is_int16(rs.offset() + kMipsLwlOffset)) {
+      if (!rd.is(rs.rm())) {
+        lwr(rd, MemOperand(rs.rm(), rs.offset() + kMipsLwrOffset));
+        lwl(rd, MemOperand(rs.rm(), rs.offset() + kMipsLwlOffset));
+      } else {
+        lwr(at, MemOperand(rs.rm(), rs.offset() + kMipsLwrOffset));
+        lwl(at, MemOperand(rs.rm(), rs.offset() + kMipsLwlOffset));
+        mov(rd, at);
+      }
+    } else {  // Offset > 16 bits, use multiple instructions to load.
+      LoadRegPlusOffsetToAt(rs);
+      lwr(rd, MemOperand(at, kMipsLwrOffset));
+      lwl(rd, MemOperand(at, kMipsLwlOffset));
+    }
+  }
 }
 
 
 void MacroAssembler::Usw(Register rd, const MemOperand& rs) {
-  swr(rd, rs);
-  swl(rd, MemOperand(rs.rm(), rs.offset() + 3));
+  DCHECK(!rd.is(at));
+  DCHECK(!rs.rm().is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    sw(rd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    if (is_int16(rs.offset() + kMipsSwrOffset) &&
+        is_int16(rs.offset() + kMipsSwlOffset)) {
+      swr(rd, MemOperand(rs.rm(), rs.offset() + kMipsSwrOffset));
+      swl(rd, MemOperand(rs.rm(), rs.offset() + kMipsSwlOffset));
+    } else {
+      LoadRegPlusOffsetToAt(rs);
+      swr(rd, MemOperand(at, kMipsSwrOffset));
+      swl(rd, MemOperand(at, kMipsSwlOffset));
+    }
+  }
+}
+
+void MacroAssembler::Ulh(Register rd, const MemOperand& rs) {
+  DCHECK(!rd.is(at));
+  DCHECK(!rs.rm().is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    lh(rd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    if (is_int16(rs.offset()) && is_int16(rs.offset() + 1)) {
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+      lbu(at, rs);
+      lb(rd, MemOperand(rs.rm(), rs.offset() + 1));
+#elif defined(V8_TARGET_BIG_ENDIAN)
+      lbu(at, MemOperand(rs.rm(), rs.offset() + 1));
+      lb(rd, rs);
+#endif
+    } else {  // Offset > 16 bits, use multiple instructions to load.
+      LoadRegPlusOffsetToAt(rs);
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+      lb(rd, MemOperand(at, 1));
+      lbu(at, MemOperand(at, 0));
+#elif defined(V8_TARGET_BIG_ENDIAN)
+      lb(rd, MemOperand(at, 0));
+      lbu(at, MemOperand(at, 1));
+#endif
+    }
+    sll(rd, rd, 8);
+    or_(rd, rd, at);
+  }
+}
+
+void MacroAssembler::Ulhu(Register rd, const MemOperand& rs) {
+  DCHECK(!rd.is(at));
+  DCHECK(!rs.rm().is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    lhu(rd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    if (is_int16(rs.offset()) && is_int16(rs.offset() + 1)) {
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+      lbu(at, rs);
+      lbu(rd, MemOperand(rs.rm(), rs.offset() + 1));
+#elif defined(V8_TARGET_BIG_ENDIAN)
+      lbu(at, MemOperand(rs.rm(), rs.offset() + 1));
+      lbu(rd, rs);
+#endif
+    } else {  // Offset > 16 bits, use multiple instructions to load.
+      LoadRegPlusOffsetToAt(rs);
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+      lbu(rd, MemOperand(at, 1));
+      lbu(at, MemOperand(at, 0));
+#elif defined(V8_TARGET_BIG_ENDIAN)
+      lbu(rd, MemOperand(at, 0));
+      lbu(at, MemOperand(at, 1));
+#endif
+    }
+    sll(rd, rd, 8);
+    or_(rd, rd, at);
+  }
+}
+
+void MacroAssembler::Ush(Register rd, const MemOperand& rs, Register scratch) {
+  DCHECK(!rd.is(at));
+  DCHECK(!rs.rm().is(at));
+  DCHECK(!rs.rm().is(scratch));
+  DCHECK(!scratch.is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    sh(rd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    MemOperand source = rs;
+    // If offset > 16 bits, load address to at with offset 0.
+    if (!is_int16(rs.offset()) || !is_int16(rs.offset() + 1)) {
+      LoadRegPlusOffsetToAt(rs);
+      source = MemOperand(at, 0);
+    }
+
+    if (!scratch.is(rd)) {
+      mov(scratch, rd);
+    }
+
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+    sb(scratch, source);
+    srl(scratch, scratch, 8);
+    sb(scratch, MemOperand(source.rm(), source.offset() + 1));
+#elif defined(V8_TARGET_BIG_ENDIAN)
+    sb(scratch, MemOperand(source.rm(), source.offset() + 1));
+    srl(scratch, scratch, 8);
+    sb(scratch, source);
+#endif
+  }
+}
+
+void MacroAssembler::Ulwc1(FPURegister fd, const MemOperand& rs,
+                           Register scratch) {
+  if (IsMipsArchVariant(kMips32r6)) {
+    lwc1(fd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    Ulw(scratch, rs);
+    mtc1(scratch, fd);
+  }
+}
+
+void MacroAssembler::Uswc1(FPURegister fd, const MemOperand& rs,
+                           Register scratch) {
+  if (IsMipsArchVariant(kMips32r6)) {
+    swc1(fd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    mfc1(scratch, fd);
+    Usw(scratch, rs);
+  }
+}
+
+void MacroAssembler::Uldc1(FPURegister fd, const MemOperand& rs,
+                           Register scratch) {
+  DCHECK(!scratch.is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    ldc1(fd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    Ulw(scratch, MemOperand(rs.rm(), rs.offset() + Register::kMantissaOffset));
+    mtc1(scratch, fd);
+    Ulw(scratch, MemOperand(rs.rm(), rs.offset() + Register::kExponentOffset));
+    Mthc1(scratch, fd);
+  }
+}
+
+void MacroAssembler::Usdc1(FPURegister fd, const MemOperand& rs,
+                           Register scratch) {
+  DCHECK(!scratch.is(at));
+  if (IsMipsArchVariant(kMips32r6)) {
+    sdc1(fd, rs);
+  } else {
+    DCHECK(IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r1) ||
+           IsMipsArchVariant(kLoongson));
+    mfc1(scratch, fd);
+    Usw(scratch, MemOperand(rs.rm(), rs.offset() + Register::kMantissaOffset));
+    Mfhc1(scratch, fd);
+    Usw(scratch, MemOperand(rs.rm(), rs.offset() + Register::kExponentOffset));
+  }
 }
 
 
 void MacroAssembler::li(Register dst, Handle<Object> value, LiFlags mode) {
   AllowDeferredHandleDereference smi_check;
   if (value->IsSmi()) {
     li(dst, Operand(value), mode);
   } else {
     DCHECK(value->IsHeapObject());
     if (isolate()->heap()->InNewSpace(*value)) {
@@ skipping 5316 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_MIPS