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[Patch] PR 61662

As requested, I am posting this patch to gcc-patches.

Problem description:
The detailed description and examples can be found in pr61662, but in short: using "#ifdef __x86_64__" to determine the size of a 'long' does not reliably yield the correct result. This causes _lrotl and _lrotr to return incorrect results on LLP64 systems (like Windows).

2014-07-09  David Wohlferd <>

        PR target/61662
        * config/i386/ia32intrin.h: Use __LP64__ to determine size of long

Index: ia32intrin.h
--- ia32intrin.h	(revision 212190)
+++ ia32intrin.h	(working copy)
@@ -256,11 +256,7 @@
 #define _bswap64(a)		__bswapq(a)
 #define _popcnt64(a)		__popcntq(a)
-#define _lrotl(a,b)		__rolq((a), (b))
-#define _lrotr(a,b)		__rorq((a), (b))
-#define _lrotl(a,b)		__rold((a), (b))
-#define _lrotr(a,b)		__rord((a), (b))
 /* Read flags register */
 extern __inline unsigned int
@@ -280,6 +276,15 @@
+/* on LP64 systems, longs are 64bits.  Use the appropriate rotate function */
+#ifdef __LP64__
+#define _lrotl(a,b)		__rolq((a), (b))
+#define _lrotr(a,b)		__rorq((a), (b))
+#define _lrotl(a,b)		__rold((a), (b))
+#define _lrotr(a,b)		__rord((a), (b))
 #define _bit_scan_forward(a)	__bsfd(a)
 #define _bit_scan_reverse(a)	__bsrd(a)
 #define _bswap(a)		__bswapd(a)

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