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| author | Xavier Leroy <xavier.leroy@inria.fr> | 2015-03-15 17:07:36 +0100 |
|---|---|---|
| committer | Xavier Leroy <xavier.leroy@inria.fr> | 2015-03-15 17:07:36 +0100 |
| commit | 57d3627c69a812a037d2d4161941ce25d15082d1 (patch) | |
| tree | 02f375b130eb6cdab00796fc3580d56684f95a70 /cfrontend/Ctyping.v | |
| parent | b3294fbaf50539f254ff3bb7145e848b3f902f73 (diff) | |
| download | compcert-kvx-57d3627c69a812a037d2d4161941ce25d15082d1.tar.gz compcert-kvx-57d3627c69a812a037d2d4161941ce25d15082d1.zip | |
Revised semantics of comparisons between a pointer and 0.
It used to be that a pointer value (Vptr) always compare unequal to the
null pointer (Vint Int.zero). However, this may not be true in the
final machine code when pointer addition overflows and wraps around
to the bit pattern 0. This patch checks the validity of the pointer
being compared with 0, and makes the comparison undefined if the
pointer is out of bounds.
Note: only the IA32 back-end was updated, ARM and PowerPC need updating.
Diffstat (limited to 'cfrontend/Ctyping.v')
| -rw-r--r-- | cfrontend/Ctyping.v | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/cfrontend/Ctyping.v b/cfrontend/Ctyping.v index 43d34007..bdeeff2a 100644 --- a/cfrontend/Ctyping.v +++ b/cfrontend/Ctyping.v @@ -1390,7 +1390,6 @@ Proof. destruct (Float.cmp Ceq f Float.zero); constructor; auto with ty. destruct (Float32.cmp Ceq f Float32.zero); constructor; auto with ty. destruct (Int.eq i Int.zero); constructor; auto with ty. - constructor; auto with ty. destruct (Int64.eq i Int64.zero); constructor; auto with ty. - (* notint *) unfold sem_notint in SEM; DestructCases; auto with ty. |