Propagated information from the reduction tactics to the kernel so

that the kernel conversion solves the delta/delta critical pair the
same way the tactics did. This allows to improve Qed time when slow
down is due to conversion having (arbitrarily) made the wrong choice.
Propagation is done thanks to a new kind of cast called REVERTcast.

Notes:
- Vm conversion not modified
- size of vo generally grows because of additional casts
- this remains a heuristic... for the record, when a reduction tactic
  is applied on the goal t leading to new goal t', this is translated
  in the kernel in a conversion t' <= t where, hence, reducing in t'
  must be preferred; what the propagation of reduction cast to the
  kernel does not do is whether it is preferable to first unfold c or
  to first compare u' and u in "c u' = c u"; in particular,
  intermediate casts are sometimes useful to solve this kind of issues
  (this is the case e.g. in Nijmegen/LinAlg/subspace_dim.v where the
  combination "simpl;red" needs the intermediate cast to ensure Qed
  answers quickly); henceforth the merge of nested casts in mkCast is
  deactivated
- for tactic "change", REVERTcast should be used when conversion is in
  the hypotheses, but convert_hyp does not (yet) support this (would
  require e.g. that convert_hyp overwrite some given hyp id with a
  body-cleared let-binding new_id := Cast(old_id,REVERTCast,t))

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@14407 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 3 insertions, 3 deletions

diff --git a/kernel/vconv.ml b/kernel/vconv.ml
index bf3640e35..4d0edc689 100644
--- a/kernel/vconv.ml
+++ b/kernel/vconv.ml
@@ -100,7 +100,7 @@ and conv_atom pb k a1 stk1 a2 stk2 cu =
 	    conv_stack k stk1 stk2 cu
 	  else raise NotConvertible
 	with NotConvertible ->
-	  if oracle_order ik1 ik2 then
+	  if oracle_order false ik1 ik2 then
             conv_whd pb k (whd_stack v1 stk1) (Vatom_stk(a2,stk2)) cu
           else conv_whd pb k (Vatom_stk(a1,stk1)) (whd_stack v2 stk2) cu
       end
@@ -236,8 +236,8 @@ let use_vm = ref false
 
 let set_use_vm b =
   use_vm := b;
-  if b then Reduction.set_default_conv vconv
-  else Reduction.set_default_conv Reduction.conv_cmp
+  if b then Reduction.set_default_conv (fun cv_pb ?(l2r=false) -> vconv cv_pb)
+  else Reduction.set_default_conv (fun cv_pb ?(l2r=false) -> Reduction.conv_cmp cv_pb)
 
 let use_vm _ = !use_vm