[compiler-rt] r204556 - InstrProf: Indicate pointer size in raw profile
Duncan P. N. Exon Smith
dexonsmith at apple.com
Sat Mar 22 20:38:05 PDT 2014
Author: dexonsmith
Date: Sat Mar 22 22:38:05 2014
New Revision: 204556
URL: http://llvm.org/viewvc/llvm-project?rev=204556&view=rev
Log:
InstrProf: Indicate pointer size in raw profile
Since the profile can come from 32-bit machines, the reader needs to
check the pointer size. Change the magic number to facilitate this.
<rdar://problem/16400648>
Modified:
compiler-rt/trunk/lib/profile/InstrProfiling.c
Modified: compiler-rt/trunk/lib/profile/InstrProfiling.c
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/profile/InstrProfiling.c?rev=204556&r1=204555&r2=204556&view=diff
==============================================================================
--- compiler-rt/trunk/lib/profile/InstrProfiling.c (original)
+++ compiler-rt/trunk/lib/profile/InstrProfiling.c Sat Mar 22 22:38:05 2014
@@ -14,11 +14,13 @@ uint64_t __llvm_profile_get_magic(void)
/* Magic number to detect file format and endianness.
*
* Use 255 at one end, since no UTF-8 file can use that character. Avoid 0,
- * so that utilities like strings doesn't grab it as a string. 129 is high
- * enough to be interesting.
+ * so that utilities, like strings, don't grab it as a string. 129 is also
+ * invalid UTF-8, and high enough to be interesting.
*
- * Use "lprofr" in the centre to stand for "LLVM Profile Raw".
+ * Use "lprofr" in the centre to stand for "LLVM Profile Raw", or "lprofR"
+ * for 32-bit platforms.
*/
+ unsigned char R = sizeof(void *) == sizeof(uint64_t) ? 'r' : 'R';
return
(uint64_t)255 << 56 |
(uint64_t)'l' << 48 |
@@ -26,7 +28,7 @@ uint64_t __llvm_profile_get_magic(void)
(uint64_t)'r' << 32 |
(uint64_t)'o' << 24 |
(uint64_t)'f' << 16 |
- (uint64_t)'r' << 8 |
+ (uint64_t) R << 8 |
(uint64_t)129;
}
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