diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/cfgexpand.c | 14 |
2 files changed, 18 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 850e31f..845f268 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,11 @@ 2009-11-26 Bernd Schmidt <bernd.schmidt@analog.com> + * cfgexpand (n_stack_vars_conflict): New static variable. + (triangular_index): Reduce likelyhood of overflow by performing + the division before the multiplication. + (resize_stack_vars_conflict): Call fatal_error if overflow + occurred in triangular_index. Update n_stack_vars_conflict. + PR rtl-opt/38582 * regrename.c (struct du_chain): Remove member earlyclobber. (scan_rtx_reg): Don't set it. Remove argument earlyclobber, diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c index 087b624..d3637a0 100644 --- a/gcc/cfgexpand.c +++ b/gcc/cfgexpand.c @@ -217,6 +217,7 @@ static size_t *stack_vars_sorted; is lower triangular. */ static bool *stack_vars_conflict; static size_t stack_vars_conflict_alloc; +static size_t n_stack_vars_conflict; /* The phase of the stack frame. This is the known misalignment of virtual_stack_vars_rtx from PREFERRED_STACK_BOUNDARY. That is, @@ -335,7 +336,11 @@ triangular_index (size_t i, size_t j) size_t t; t = i, i = j, j = t; } - return (i * (i + 1)) / 2 + j; + + if (i & 1) + return ((i + 1) / 2) * i + j; + else + return (i / 2) * (i + 1) + j; } /* Ensure that STACK_VARS_CONFLICT is large enough for N objects. */ @@ -346,12 +351,17 @@ resize_stack_vars_conflict (size_t n) size_t size = triangular_index (n-1, n-1) + 1; if (size <= stack_vars_conflict_alloc) - return; + { + if (n > n_stack_vars_conflict) + fatal_error ("program is too large to be compiled on this machine"); + return; + } stack_vars_conflict = XRESIZEVEC (bool, stack_vars_conflict, size); memset (stack_vars_conflict + stack_vars_conflict_alloc, 0, (size - stack_vars_conflict_alloc) * sizeof (bool)); stack_vars_conflict_alloc = size; + n_stack_vars_conflict = n; } /* Make the decls associated with luid's X and Y conflict. */ |