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| author | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2018-08-09 17:53:18 +0200 |
|---|---|---|
| committer | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2018-08-25 21:04:11 +0200 |
| commit | cf773f6cf67c88731a77be96245b2a1600de94ff (patch) | |
| tree | 2446b5aadb235ac5c9eb3f3d4408da7c43c7f156 | |
| parent | 418aa1fe4bd938f9028ef1f2a71bea56aa9ab3ad (diff) | |
| download | sparse-dev-cf773f6cf67c88731a77be96245b2a1600de94ff.tar.gz | |
fix: do not optimize away accesses to volatile bitfields
Accesses to volatiles must, of course, not be optimized away.
For this, we need to check to type associated to the memory access.
Currently this is done by checking if the type of the result of
the memops is volatile or not. Usualy, the type of the result is
the same as the one of the access so everything is good but for
bitfields, the memop is not done with the type of the bitfield
itself but to its base type. Since this base type is unrelated
to the access type, it is generaly not marked as volatile even
when the access to the bitfield is volatile.
Fix this by using the true type of the access to set the field
struct instruction::is_volatile.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
| -rw-r--r-- | linearize.c | 4 | ||||
| -rw-r--r-- | validation/optim/volatile-bitfield.c | 1 |
2 files changed, 2 insertions, 3 deletions
diff --git a/linearize.c b/linearize.c index fc4c4271..c4f38456 100644 --- a/linearize.c +++ b/linearize.c @@ -991,7 +991,7 @@ static pseudo_t add_load(struct entrypoint *ep, struct access_data *ad) insn->target = new; insn->offset = ad->offset; - insn->is_volatile = insn->type && (insn->type->ctype.modifiers & MOD_VOLATILE); + insn->is_volatile = ad->type && (ad->type->ctype.modifiers & MOD_VOLATILE); use_pseudo(insn, ad->address, &insn->src); add_one_insn(ep, insn); return new; @@ -1007,7 +1007,7 @@ static void add_store(struct entrypoint *ep, struct access_data *ad, pseudo_t va store = alloc_typed_instruction(OP_STORE, ad->btype); store->offset = ad->offset; - store->is_volatile = store->type && (store->type->ctype.modifiers & MOD_VOLATILE); + store->is_volatile = ad->type && (ad->type->ctype.modifiers & MOD_VOLATILE); use_pseudo(store, value, &store->target); use_pseudo(store, ad->address, &store->src); add_one_insn(ep, store); diff --git a/validation/optim/volatile-bitfield.c b/validation/optim/volatile-bitfield.c index c28efb09..99db4401 100644 --- a/validation/optim/volatile-bitfield.c +++ b/validation/optim/volatile-bitfield.c @@ -10,7 +10,6 @@ void foo(volatile struct s *p) /* * check-name: volatile-bitfield * check-command: test-linearize -Wno-decl $file - * check-known-to-fail * * check-output-ignore * check-output-contains: load\\. |