diff options
Diffstat (limited to 'gcc/calls.c')
| -rw-r--r-- | gcc/calls.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/gcc/calls.c b/gcc/calls.c index df6699a29bd..45001c08ee7 100644 --- a/gcc/calls.c +++ b/gcc/calls.c @@ -1239,13 +1239,25 @@ precompute_arguments (int flags, int num_actuals, struct arg_data *args) /* If this is a libcall, then precompute all arguments so that we do not get extraneous instructions emitted as part of the libcall sequence. */ - if ((flags & ECF_LIBCALL_BLOCK) == 0) + + /* If we preallocated the stack space, and some arguments must be passed + on the stack, then we must precompute any parameter which contains a + function call which will store arguments on the stack. + Otherwise, evaluating the parameter may clobber previous parameters + which have already been stored into the stack. (we have code to avoid + such case by saving the outgoing stack arguments, but it results in + worse code) */ + if ((flags & ECF_LIBCALL_BLOCK) == 0 && !ACCUMULATE_OUTGOING_ARGS) return; for (i = 0; i < num_actuals; i++) { enum machine_mode mode; + if ((flags & ECF_LIBCALL_BLOCK) == 0 + && TREE_CODE (args[i].tree_value) != CALL_EXPR) + continue; + /* If this is an addressable type, we cannot pre-evaluate it. */ gcc_assert (!TREE_ADDRESSABLE (TREE_TYPE (args[i].tree_value))); |