eal/x86: fix type of variable in memcpy function

GCC 8.1 warned:

rte_memcpy.h:793:2: note: in expansion of macro 'MOVEUNALIGNED_LEFT47'
  MOVEUNALIGNED_LEFT47(dst, src, n, srcofs);
  ^~~~~~~~~~~~~~~~~~~~
rte_memcpy.h:649:51: warning: conversion from 'size_t'
{aka 'long unsigned int'} to 'int' may change value [-Wconversion]
     case 0x0B: MOVEUNALIGNED_LEFT47_IMM(dst, src, n, 0x0B); break;
                                                   ^

rte_memcpy.h:616:15: note: in definition of macro 'MOVEUNALIGNED_LEFT47_IMM'
         tmp = len;
               ^~~
rte_memcpy.h:793:2: note: in expansion of macro 'MOVEUNALIGNED_LEFT47'
  MOVEUNALIGNED_LEFT47(dst, src, n, srcofs);
  ^~~~~~~~~~~~~~~~~~~~
rte_memcpy.h:618:13: warning: conversion to 'size_t'
{aka 'long unsigned int'} from 'int'
may change the sign of the result [-Wsign-conversion]
         tmp -= len;
             ^~

rte_memcpy.h:649:16: note: in expansion of macro 'MOVEUNALIGNED_LEFT47_IMM'
     case 0x0B: MOVEUNALIGNED_LEFT47_IMM(dst, src, n, 0x0B); break;
                ^~~~~~~~~~~~~~~~~~~~~~~~
rte_memcpy.h:793:2: note: in expansion of macro 'MOVEUNALIGNED_LEFT47'
  MOVEUNALIGNED_LEFT47(dst, src, n, srcofs);
  ^~~~~~~~~~~~~~~~~~~~
rte_memcpy.h:618:13: warning: conversion to 'size_t'
{aka 'long unsigned int'} from 'int'
may change the sign of the result [-Wsign-conversion]
             tmp -= len;
                 ^~

We can eliminate the problems by setting the type of tmp to
size_t in the first place.

Fixes: d35cc1fe6a ("eal/x86: revert select optimized memcpy at run-time")
Cc: stable@dpdk.org
Suggested-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Andy Green <andy@warmcat.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>

diff --git a/lib/librte_eal/common/include/arch/x86/rte_memcpy.h b/lib/librte_eal/common/include/arch/x86/rte_memcpy.h
index 5ead68a..7b75809 100644 (file)
--- a/lib/librte_eal/common/include/arch/x86/rte_memcpy.h
+++ b/lib/librte_eal/common/include/arch/x86/rte_memcpy.h
@@ -574,7 +574,7 @@ rte_mov256(uint8_t *dst, const uint8_t *src)
  */
 #define MOVEUNALIGNED_LEFT47_IMM(dst, src, len, offset)                                                     \
 __extension__ ({                                                                                            \
-    int tmp;                                                                                                \
+    size_t tmp;                                                                                                \
     while (len >= 128 + 16 - offset) {                                                                      \
         xmm0 = _mm_loadu_si128((const __m128i *)((const uint8_t *)src - offset + 0 * 16));                  \
         len -= 128;                                                                                         \