mirror/gcc
2
0
Fork 0
mirror of git://gcc.gnu.org/git/gcc.git synced 2025-04-05 09:50:42 +08:00
Code Issues Packages Projects Releases Wiki Activity

Fix UBSAN error, shifting 64 bit value by 64.

Browse Source 
2020-03-13  Aaron Sawdey  <acsawdey@linux.ibm.com>

	PR target/92379
	* config/rs6000/rs6000.c (num_insns_constant_multi) Don't shift a
	64-bit value by 64 bits (UB).
This commit is contained in:
Aaron Sawdey 2020-03-13 18:14:22 -05:00
parent 5c048755ec
commit 50c96067c8
2 changed files with 10 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
gcc/ChangeLog
View File

@ -1,3 +1,9 @@
2020-03-13 Aaron Sawdey <acsawdey@linux.ibm.com>
PR target/92379
* config/rs6000/rs6000.c (num_insns_constant_multi) Don't shift a
64-bit value by 64 bits (UB).
2020-03-13 Vladimir Makarov <vmakarov@redhat.com>
PR rtl-optimization/92303

5
gcc/config/rs6000/rs6000.c
View File

@ -5612,7 +5612,10 @@ num_insns_constant_multi (HOST_WIDE_INT value, machine_mode mode)
&& rs6000_is_valid_and_mask (GEN_INT (low), DImode))
insns = 2;
total += insns;
value >>= BITS_PER_WORD;
/* If BITS_PER_WORD is the number of bits in HOST_WIDE_INT, doing
it all at once would be UB. */
value >>= (BITS_PER_WORD - 1);
value >>= 1;
}
return total;
}