@@ -64,6 +64,7 @@ along with GCC; see the file COPYING3. If not see
#include "analyzer/bar-chart.h"
#include <zlib.h>
#include "plugin.h"
+#include "target.h"
/* For an overview, see gcc/doc/analyzer.texi. */
@@ -4845,6 +4846,13 @@ impl_run_checkers (logger *logger)
{
LOG_SCOPE (logger);
+ if (logger)
+ {
+ logger->log ("BITS_BIG_ENDIAN: %i", BITS_BIG_ENDIAN ? 1 : 0);
+ logger->log ("BYTES_BIG_ENDIAN: %i", BYTES_BIG_ENDIAN ? 1 : 0);
+ logger->log ("WORDS_BIG_ENDIAN: %i", WORDS_BIG_ENDIAN ? 1 : 0);
+ }
+
/* If using LTO, ensure that the cgraph nodes have function bodies. */
cgraph_node *node;
FOR_EACH_FUNCTION_WITH_GIMPLE_BODY (node)
@@ -431,6 +431,60 @@ region_model_manager::get_or_create_cast (tree type, const svalue *arg)
return get_or_create_unaryop (type, op, arg);
}
+/* Subroutine of region_model_manager::maybe_fold_binop for handling
+ (TYPE)(COMPOUND_SVAL BIT_AND_EXPR CST) that may have been generated by
+ optimize_bit_field_compare, where CST is from ARG1.
+
+ Support masking out bits from a compound_svalue for comparing a bitfield
+ against a value, as generated by optimize_bit_field_compare for
+ BITFIELD == VALUE.
+
+ If COMPOUND_SVAL has a value for the appropriate bits, return it,
+ shifted accordingly.
+ Otherwise return NULL. */
+
+const svalue *
+region_model_manager::
+maybe_undo_optimize_bit_field_compare (tree type,
+ const compound_svalue *compound_sval,
+ tree cst,
+ const svalue *arg1)
+{
+ if (type != unsigned_char_type_node)
+ return NULL;
+
+ const binding_map &map = compound_sval->get_map ();
+ unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (cst);
+ /* If "mask" is a contiguous range of set bits, see if the
+ compound_sval has a value for those bits. */
+ bit_range bits (0, 0);
+ if (!bit_range::from_mask (mask, &bits))
+ return NULL;
+
+ bit_range bound_bits (bits);
+ if (BYTES_BIG_ENDIAN)
+ bound_bits = bit_range (BITS_PER_UNIT - bits.get_next_bit_offset (),
+ bits.m_size_in_bits);
+ const concrete_binding *conc
+ = get_store_manager ()->get_concrete_binding (bound_bits, BK_direct);
+ const svalue *sval = map.get (conc);
+ if (!sval)
+ return NULL;
+
+ /* We have a value;
+ shift it by the correct number of bits. */
+ const svalue *lhs = get_or_create_cast (type, sval);
+ HOST_WIDE_INT bit_offset = bits.get_start_bit_offset ().to_shwi ();
+ tree shift_amt = build_int_cst (type, bit_offset);
+ const svalue *shift_sval = get_or_create_constant_svalue (shift_amt);
+ const svalue *shifted_sval = get_or_create_binop (type, LSHIFT_EXPR,
+ lhs, shift_sval);
+ /* Reapply the mask (needed for negative
+ signed bitfields). */
+ return get_or_create_binop (type, BIT_AND_EXPR,
+ shifted_sval, arg1);
+}
+
/* Subroutine of region_model_manager::get_or_create_binop.
Attempt to fold the inputs and return a simpler svalue *.
Otherwise, return NULL. */
@@ -485,43 +539,13 @@ region_model_manager::maybe_fold_binop (tree type, enum tree_code op,
/* "(ARG0 & 0)" -> "0". */
return get_or_create_constant_svalue (build_int_cst (type, 0));
- /* Support masking out bits from a compound_svalue, as this
- is generated when accessing bitfields. */
if (const compound_svalue *compound_sval
= arg0->dyn_cast_compound_svalue ())
- {
- const binding_map &map = compound_sval->get_map ();
- unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (cst1);
- /* If "mask" is a contiguous range of set bits, see if the
- compound_sval has a value for those bits. */
- bit_range bits (0, 0);
- if (bit_range::from_mask (mask, &bits))
- {
- const concrete_binding *conc
- = get_store_manager ()->get_concrete_binding (bits,
- BK_direct);
- if (const svalue *sval = map.get (conc))
- {
- /* We have a value;
- shift it by the correct number of bits. */
- const svalue *lhs = get_or_create_cast (type, sval);
- HOST_WIDE_INT bit_offset
- = bits.get_start_bit_offset ().to_shwi ();
- tree shift_amt = build_int_cst (type, bit_offset);
- const svalue *shift_sval
- = get_or_create_constant_svalue (shift_amt);
- const svalue *shifted_sval
- = get_or_create_binop (type,
- LSHIFT_EXPR,
- lhs, shift_sval);
- /* Reapply the mask (needed for negative
- signed bitfields). */
- return get_or_create_binop (type,
- BIT_AND_EXPR,
- shifted_sval, arg1);
- }
- }
- }
+ if (const svalue *sval
+ = maybe_undo_optimize_bit_field_compare (type,
+ compound_sval,
+ cst1, arg1))
+ return sval;
}
break;
case TRUTH_ANDIF_EXPR:
@@ -320,6 +320,9 @@ private:
const svalue *maybe_fold_sub_svalue (tree type,
const svalue *parent_svalue,
const region *subregion);
+ const svalue *maybe_undo_optimize_bit_field_compare (tree type,
+ const compound_svalue *compound_sval,
+ tree cst, const svalue *arg1);
unsigned m_next_region_id;
root_region m_root_region;
@@ -249,6 +249,18 @@ bit_range::dump_to_pp (pretty_printer *pp) const
pp_wide_int (pp, get_next_bit_offset (), SIGNED);
}
+/* Dump this object to stderr. */
+
+DEBUG_FUNCTION void
+bit_range::dump () const
+{
+ pretty_printer pp;
+ pp.buffer->stream = stderr;
+ dump_to_pp (&pp);
+ pp_newline (&pp);
+ pp_flush (&pp);
+}
+
int
bit_range::cmp (const bit_range &br1, const bit_range &br2)
{
@@ -275,6 +275,7 @@ struct bit_range
{}
void dump_to_pp (pretty_printer *pp) const;
+ void dump () const;
bit_offset_t get_start_bit_offset () const
{
Looks like my patch for PR analyzer/99212 implicitly assumed little-endian, which the following patch fixes. Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu. I attempted to test it on all targets using config-list.mk but repeatedly managed to delete everything by mistake, so for now I've merely verified that this fixes bitfields-1.c on: - armeb-none-linux-gnueabihf - cris-elf - powerpc64-darwin - s390-linux-gnu Pushed to trunk as r12-1491-gec3fafa9ec7d16b9d89076efd3bac1d1af0502b8. Sorry about the breakage. gcc/analyzer/ChangeLog: PR analyzer/99212 PR analyzer/101082 * engine.cc: Include "target.h". (impl_run_checkers): Log BITS_BIG_ENDIAN, BYTES_BIG_ENDIAN, and WORDS_BIG_ENDIAN. * region-model-manager.cc (region_model_manager::maybe_fold_binop): Move support for masking via ARG0 & CST into... (region_model_manager::maybe_undo_optimize_bit_field_compare): ...this new function. Flatten by converting from nested conditionals to a series of early return statements to reject failures. Reject if type is not unsigned_char_type_node. Handle BYTES_BIG_ENDIAN when determining which bits are bound in the binding_map. * region-model.h (region_model_manager::maybe_undo_optimize_bit_field_compare): New decl. * store.cc (bit_range::dump): New function. * store.h (bit_range::dump): New decl. Signed-off-by: David Malcolm <dmalcolm@redhat.com> --- gcc/analyzer/engine.cc | 8 +++ gcc/analyzer/region-model-manager.cc | 94 +++++++++++++++++----------- gcc/analyzer/region-model.h | 3 + gcc/analyzer/store.cc | 12 ++++ gcc/analyzer/store.h | 1 + 5 files changed, 83 insertions(+), 35 deletions(-)