On 11/13/14 15:59, Mike Stump wrote:
The problem, since this is a hook now, one can’t just test ifdef
FUNCTION_PROLOGUE.
Right, but we can test the existence of the expander via the HAVE_xxx
interface.
What that can't test is the expander failing (via FAIL;). But the
prologue/epilogue expanders are't on the list of expanders allowed to
use FAIL.
@findex FAIL
@item FAIL
Make the pattern fail on this occasion. When a pattern fails, it means
that the pattern was not truly available. The calling routines in the
compiler will try other strategies for code generation using other patterns.
Failure is currently supported only for binary (addition, multiplication,
shifting, etc.) and bit-field (@code{extv}, @code{extzv}, and @code{insv})
operations.
Jeff
