#include "gimple-pretty-print.h"
#include "gimple-range.h"
#include "tree-cfg.h"
+#include "target.h"
+#include "attribs.h"
+#include "gimple-iterator.h"
+#include "gimple-walk.h"
#define DEBUG_RANGE_CACHE (dump_file \
&& (param_ranger_debug & RANGER_DEBUG_CACHE))
m_nn.release ();
}
+// This routine will update NAME in BB to be nonnull if it is not already.
+// return TRUE if the update happens.
+
+bool
+non_null_ref::set_nonnull (basic_block bb, tree name)
+{
+ gcc_checking_assert (gimple_range_ssa_p (name)
+ && POINTER_TYPE_P (TREE_TYPE (name)));
+ // Only process when its not already set.
+ if (non_null_deref_p (name, bb, false))
+ return false;
+ bitmap_set_bit (m_nn[SSA_NAME_VERSION (name)], bb->index);
+ return true;
+}
+
// Return true if NAME has a non-null dereference in block bb. If this is the
// first query for NAME, calculate the summary first.
// If SEARCH_DOM is true, the search the dominator tree as well.
return false;
}
-// If NAME has a non-null dereference in block BB, adjust R with the
-// non-zero information from non_null_deref_p, and return TRUE. If
-// SEARCH_DOM is true, non_null_deref_p should search the dominator tree.
-
-bool
-non_null_ref::adjust_range (irange &r, tree name, basic_block bb,
- bool search_dom)
-{
- // Non-call exceptions mean we could throw in the middle of the
- // block, so just punt on those for now.
- if (cfun->can_throw_non_call_exceptions)
- return false;
-
- // We only care about the null / non-null property of pointers.
- if (!POINTER_TYPE_P (TREE_TYPE (name)))
- return false;
- if (r.undefined_p () || r.lower_bound () != 0 || r.upper_bound () == 0)
- return false;
- // Check if pointers have any non-null dereferences.
- if (non_null_deref_p (name, bb, search_dom))
- {
- // Remove zero from the range.
- unsigned prec = TYPE_PRECISION (TREE_TYPE (name));
- r.intersect (wi::one (prec), wi::max_value (prec, UNSIGNED));
- return true;
- }
- return false;
-}
-
// Allocate an populate the bitmap for NAME. An ON bit for a block
// index indicates there is a non-null reference in that block. In
// order to populate the bitmap, a quick run of all the immediate uses
else
r = gimple_range_global (name);
}
-
- if (bb)
- m_non_null.adjust_range (r, name, bb, false);
}
// Get the range of NAME as it occurs on entry to block BB.
// Otherwise pick up the best available global value.
if (!m_on_entry.get_bb_range (r, name, bb))
range_of_def (r, name);
-
- m_non_null.adjust_range (r, name, bb, false);
}
// Get the range of NAME as it occurs on exit from block BB.
if (gimple_range_ssa_p (expr))
{
exit_range (r, expr, e->src);
+ // If this is not an abnormal edge, check for a non-null exit.
+ if ((e->flags & (EDGE_EH | EDGE_ABNORMAL)) == 0)
+ m_non_null.adjust_range (r, expr, e->src, false);
int_range_max edge_range;
if (m_gori.outgoing_edge_range_p (edge_range, e, expr, *this))
r.intersect (edge_range);
}
return true;
}
+
+// This routine will update NAME in block BB to the nonnull state.
+// It will then update the on-entry cache for this block to be non-null
+// if it isn't already.
+
+void
+ranger_cache::update_to_nonnull (basic_block bb, tree name)
+{
+ tree type = TREE_TYPE (name);
+ if (gimple_range_ssa_p (name) && POINTER_TYPE_P (type))
+ {
+ m_non_null.set_nonnull (bb, name);
+ // Update the on-entry cache for BB to be non-zero. Note this can set
+ // the on entry value in the DEF block, which can override the def.
+ int_range_max r;
+ exit_range (r, name, bb);
+ if (r.varying_p ())
+ {
+ r.set_nonzero (type);
+ m_on_entry.set_bb_range (name, bb, r);
+ }
+ }
+}
+
+// Adapted from infer_nonnull_range_by_dereference and check_loadstore
+// to process nonnull ssa_name OP in S. DATA contains the ranger_cache.
+
+static bool
+non_null_loadstore (gimple *s, tree op, tree, void *data)
+{
+ if (TREE_CODE (op) == MEM_REF || TREE_CODE (op) == TARGET_MEM_REF)
+ {
+ /* Some address spaces may legitimately dereference zero. */
+ addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (op));
+ if (!targetm.addr_space.zero_address_valid (as))
+ {
+ tree ssa = TREE_OPERAND (op, 0);
+ basic_block bb = gimple_bb (s);
+ ((ranger_cache *)data)->update_to_nonnull (bb, ssa);
+ }
+ }
+ return false;
+}
+
+// This routine is used during a block walk to move the state of non-null for
+// any operands on stmt S to nonnull.
+
+void
+ranger_cache::block_apply_nonnull (gimple *s)
+{
+ if (!flag_delete_null_pointer_checks)
+ return;
+ if (is_a<gphi *> (s))
+ return;
+ if (gimple_code (s) == GIMPLE_ASM || gimple_clobber_p (s))
+ return;
+ if (is_a<gcall *> (s))
+ {
+ tree fntype = gimple_call_fntype (s);
+ bitmap nonnullargs = get_nonnull_args (fntype);
+ // Process any non-null arguments
+ if (nonnullargs)
+ {
+ basic_block bb = gimple_bb (s);
+ for (unsigned i = 0; i < gimple_call_num_args (s); i++)
+ {
+ if (bitmap_empty_p (nonnullargs) || bitmap_bit_p (nonnullargs, i))
+ {
+ tree op = gimple_call_arg (s, i);
+ update_to_nonnull (bb, op);
+ }
+ }
+ BITMAP_FREE (nonnullargs);
+ }
+ // Fallthru and walk load/store ops now.
+ }
+ walk_stmt_load_store_ops (s, (void *)this, non_null_loadstore,
+ non_null_loadstore);
+}
bool non_null_deref_p (tree name, basic_block bb, bool search_dom = true);
bool adjust_range (irange &r, tree name, basic_block bb,
bool search_dom = true);
+ bool set_nonnull (basic_block bb, tree name);
private:
vec <bitmap> m_nn;
void process_name (tree name);
bitmap_obstack m_bitmaps;
};
+// If NAME has a non-null dereference in block BB, adjust R with the
+// non-zero information from non_null_deref_p, and return TRUE. If
+// SEARCH_DOM is true, non_null_deref_p should search the dominator tree.
+
+inline bool
+non_null_ref::adjust_range (irange &r, tree name, basic_block bb,
+ bool search_dom)
+{
+ // Non-call exceptions mean we could throw in the middle of the
+ // block, so just punt on those for now.
+ if (cfun->can_throw_non_call_exceptions)
+ return false;
+ // We only care about the null / non-null property of pointers.
+ if (!POINTER_TYPE_P (TREE_TYPE (name)))
+ return false;
+ if (r.undefined_p () || r.lower_bound () != 0 || r.upper_bound () == 0)
+ return false;
+ // Check if pointers have any non-null dereferences.
+ if (non_null_deref_p (name, bb, search_dom))
+ {
+ // Remove zero from the range.
+ unsigned prec = TYPE_PRECISION (TREE_TYPE (name));
+ r.intersect (wi::one (prec), wi::max_value (prec, UNSIGNED));
+ return true;
+ }
+ return false;
+}
+
// This class manages a vector of pointers to ssa_block ranges. It
// provides the basis for the "range on entry" cache for all
// SSA names.
void propagate_updated_value (tree name, basic_block bb);
+ void block_apply_nonnull (gimple *s);
+ void update_to_nonnull (basic_block bb, tree name);
non_null_ref m_non_null;
gori_compute m_gori;
#include "tree-scalar-evolution.h"
#include "gimple-range.h"
#include "gimple-fold.h"
+#include "gimple-walk.h"
gimple_ranger::gimple_ranger () :
non_executable_edge_flag (cfun),
// If name is defined in this block, try to get an range from S.
if (def_stmt && gimple_bb (def_stmt) == bb)
{
- range_of_stmt (r, def_stmt, expr);
- m_cache.m_non_null.adjust_range (r, expr, bb, true);
+ // Check for a definition override from a block walk.
+ if (!POINTER_TYPE_P (TREE_TYPE (expr))
+ || !m_cache.block_range (r, bb, expr, false))
+ range_of_stmt (r, def_stmt, expr);
}
// Otherwise OP comes from outside this block, use range on entry.
else
if (m_cache.block_range (entry_range, bb, name))
r.intersect (entry_range);
- m_cache.m_non_null.adjust_range (r, name, bb, true);
+ if (dom_info_available_p (CDI_DOMINATORS))
+ {
+ basic_block dom_bb = get_immediate_dominator (CDI_DOMINATORS, bb);
+ if (dom_bb)
+ m_cache.m_non_null.adjust_range (r, name, dom_bb, true);
+ }
if (idx)
tracer.trailer (idx, "range_on_entry", true, name, r);
else
{
range_on_exit (r, e->src, name);
+ // If this is not an abnormal edge, check for a non-null exit .
+ if ((e->flags & (EDGE_EH | EDGE_ABNORMAL)) == 0)
+ m_cache.m_non_null.adjust_range (r, name, e->src, false);
gcc_checking_assert (r.undefined_p ()
|| range_compatible_p (r.type(), TREE_TYPE (name)));
return ret;
}
+// Called during dominator walks to register any side effects that take effect
+// from this point forward. Current release is only for tracking non-null
+// within a block.
+
+void
+gimple_ranger::register_side_effects (gimple *s)
+{
+ m_cache.block_apply_nonnull (s);
+}
+
// This routine will export whatever global ranges are known to GCC
// SSA_RANGE_NAME_INFO and SSA_NAME_PTR_INFO fields.
projects / thirdparty / gcc.git / commitdiff
