Subject says it all. The JIT and static backends both execute the 176.gcc benchmark incorrectly when the local-alloc.c file is compiled with the LLVM x86 backend. All other files are compiled correctly.
bugpoint informs me that: *** The following functions are being miscompiled: find_free_reg I will investigate! Thanks bugpoint!
The X86 backend is letting computation of constant expressions in PHI nodes clobber condition code registers. Here's a testcase smaller than 176.gcc: http://mail.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20031013/008296.html
This bug is fixed: http://mail.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20031013/008297.html 176.gcc now works with the x86 backend.