Hi! libtsan only handles the standard memory model values, so I've added just in case some new unknown memory model is used bail outs (keeping the __atomic_* builtins instead of transforming them to __tsan_atomic*). Except that at -O0 (or if unlucky enough otherwise) if the memory model is variable, that means we never use __tsan_atomic*, which means libtsan reports false positive races. We could do those checks at runtime by performing if ((last_arg & 0x7fff) >= 6) __atomic_* else __tsan_atomic_*, but as there are no such values yet I think it isn't worth it (the sync/hle acq/hle rel bits which are ored are 0x8000, 0x10000 and 0x20000 and memmodel_base strips them off).
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2017-03-20 Jakub Jelinek <ja...@redhat.com> PR sanitizer/78158 * tsan.c (instrument_builtin_call): If the memory model argument is not a constant, assume it is valid. --- gcc/tsan.c.jj 2017-01-01 12:45:38.000000000 +0100 +++ gcc/tsan.c 2017-03-20 17:55:25.509294018 +0100 @@ -499,8 +499,8 @@ instrument_builtin_call (gimple_stmt_ite case check_last: case fetch_op: last_arg = gimple_call_arg (stmt, num - 1); - if (!tree_fits_uhwi_p (last_arg) - || memmodel_base (tree_to_uhwi (last_arg)) >= MEMMODEL_LAST) + if (tree_fits_uhwi_p (last_arg) + && memmodel_base (tree_to_uhwi (last_arg)) >= MEMMODEL_LAST) return; gimple_call_set_fndecl (stmt, decl); update_stmt (stmt); @@ -564,11 +564,11 @@ instrument_builtin_call (gimple_stmt_ite gcc_assert (num == 6); for (j = 0; j < 6; j++) args[j] = gimple_call_arg (stmt, j); - if (!tree_fits_uhwi_p (args[4]) - || memmodel_base (tree_to_uhwi (args[4])) >= MEMMODEL_LAST) + if (tree_fits_uhwi_p (args[4]) + && memmodel_base (tree_to_uhwi (args[4])) >= MEMMODEL_LAST) return; - if (!tree_fits_uhwi_p (args[5]) - || memmodel_base (tree_to_uhwi (args[5])) >= MEMMODEL_LAST) + if (tree_fits_uhwi_p (args[5]) + && memmodel_base (tree_to_uhwi (args[5])) >= MEMMODEL_LAST) return; update_gimple_call (gsi, decl, 5, args[0], args[1], args[2], args[4], args[5]); @@ -642,8 +642,8 @@ instrument_builtin_call (gimple_stmt_ite return; } last_arg = gimple_call_arg (stmt, num - 1); - if (!tree_fits_uhwi_p (last_arg) - || memmodel_base (tree_to_uhwi (last_arg)) >= MEMMODEL_LAST) + if (tree_fits_uhwi_p (last_arg) + && memmodel_base (tree_to_uhwi (last_arg)) >= MEMMODEL_LAST) return; t = TYPE_ARG_TYPES (TREE_TYPE (decl)); t = TREE_VALUE (TREE_CHAIN (t)); Jakub