Changeset 10995 in vbox for trunk/include

Timestamp:

Jul 30, 2008 3:49:16 PM (17 years ago)

Author:

vboxsync

Message:

iprt: Added ASMByteSwapU16/64 and unit test for them + U32.

File:

• trunk/include/iprt/asm.h (modified) (2 diffs)

trunk/include/iprt/asm.h

@@ -5540 +5540 @@
 }
 
+/**
+ * Reverse the byte order of the given 16-bit integer.
+ *
+ * @returns Revert
+ * @param   u16     16-bit integer value.
+ */
+DECLINLINE(uint16_t) ASMByteSwapU16(uint16_t u16)
+{
+#if RT_INLINE_ASM_USES_INTRIN
+    u16 = _byteswap_ushort(u16);
+#elif RT_INLINE_ASM_GNU_STYLE
+    __asm__ ("rorw $8, %0" : "=r" (u16) : "0" (u16));
+#else
+    _asm
+    {
+        mov     ax, [u16]
+        ror     ax, 8
+        mov     [u16], ax
+    }
+#endif
+    return u16;
+}
 
 /**
  * Reverse the byte order of the given 32-bit integer.
- * @param  u32      Integer
+ *
+ * @returns Revert
+ * @param   u32     32-bit integer value.
  */
 DECLINLINE(uint32_t) ASMByteSwapU32(uint32_t u32)
@@ -5562 +5586 @@
 }
 
+
+/**
+ * Reverse the byte order of the given 64-bit integer.
+ *
+ * @returns Revert
+ * @param   u64     64-bit integer value.
+ */
+DECLINLINE(uint64_t) ASMByteSwapU64(uint64_t u64)
+{
+#if defined(RT_ARCH_AMD64) && RT_INLINE_ASM_USES_INTRIN
+    u64 = _byteswap_uint64(u64);
+#else /* !RT_ARCH_AMD64 (assume x86) */
+    u64 = (uint64_t)ASMByteSwapU32((uint32_t)u64) << 32
+        | (uint64_t)ASMByteSwapU32(u64 >> 32);
+#endif
+    return u64;
+}
+
+
 /** @} */