Joseph Myers 85b647e486 target/i386: fix pcmpxstrx substring search ... One of the cases of the SSE4.2 pcmpestri / pcmpestrm / pcmpistri / pcmpistrm instructions does a substring search. The implementation of this case in the pcmpxstrx helper is incorrect. The operation in this case is a search for a string (argument d to the helper) in another string (argument s to the helper); if a copy of d at a particular position would run off the end of s, the resulting output bit should be 0 whether or not the strings match in the region where they overlap, but the QEMU implementation was wrongly comparing only up to the point where s ends and counting it as a match if an initial segment of d matched a terminal segment of s. Here, "run off the end of s" means that some byte of d would overlap some byte outside of s; thus, if d has zero length, it is considered to match everywhere, including after the end of s. This patch fixes the implementation to correspond with the proper instruction semantics. This fixes four gcc test failures in my GCC 6-based testing. Backports commit ae35eea7e4a9f21dd147406dfbcd0c4c6aaf2a60 from qemu		2018-03-04 23:58:45 -05:00
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arm	target/arm: Avoid an extra temporary for store_exclusive	2018-03-04 23:17:50 -05:00
i386	target/i386: fix pcmpxstrx substring search	2018-03-04 23:58:45 -05:00
m68k	target/m68k: Switch fpu_rom from make_floatx80() to make_floatx80_init()	2018-03-04 23:05:01 -05:00
mips	gen-icount: check cflags instead of use_icount global	2018-03-04 14:26:26 -05:00
sparc	sparc: Fix typedef clash	2018-03-04 23:05:50 -05:00