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| author | Richard Guenther <rguenther@suse.de> | 2011-07-29 09:24:23 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2011-07-29 09:24:23 +0000 |
| commit | a9b332d4faa42a781340b354d8a9f6426d6e3ebd (patch) | |
| tree | 3ff702d99bd1b72a7e57dcb5000b12ec28ee85d6 /gcc/tree-vrp.c | |
| parent | 17b3c7a2dbccfb4dcb7d78e0c974a0ad212262a9 (diff) | |
| download | gcc-a9b332d4faa42a781340b354d8a9f6426d6e3ebd.zip gcc-a9b332d4faa42a781340b354d8a9f6426d6e3ebd.tar.gz gcc-a9b332d4faa42a781340b354d8a9f6426d6e3ebd.tar.bz2 | |
tree-vrp.c (get_value_range): Only set parameter default definitions to varying, leave others at undefined.
2011-07-29 Richard Guenther <rguenther@suse.de>
* tree-vrp.c (get_value_range): Only set parameter default
definitions to varying, leave others at undefined.
(extract_range_from_binary_expr): Fix undefined handling.
(vrp_visit_phi_node): Handle merged undefined state.
* gcc.dg/uninit-suppress.c: Also disable VRP.
* gcc.dg/uninit-suppress_2.c: Likewise.
From-SVN: r176918
Diffstat (limited to 'gcc/tree-vrp.c')
| -rw-r--r-- | gcc/tree-vrp.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c index b53ef5e..15331e1 100644 --- a/gcc/tree-vrp.c +++ b/gcc/tree-vrp.c @@ -692,16 +692,16 @@ get_value_range (const_tree var) /* Defer allocating the equivalence set. */ vr->equiv = NULL; - /* If VAR is a default definition, the variable can take any value - in VAR's type. */ + /* If VAR is a default definition of a parameter, the variable can + take any value in VAR's type. */ sym = SSA_NAME_VAR (var); - if (SSA_NAME_IS_DEFAULT_DEF (var)) + if (SSA_NAME_IS_DEFAULT_DEF (var) + && TREE_CODE (sym) == PARM_DECL) { /* Try to use the "nonnull" attribute to create ~[0, 0] anti-ranges for pointers. Note that this is only valid with default definitions of PARM_DECLs. */ - if (TREE_CODE (sym) == PARM_DECL - && POINTER_TYPE_P (TREE_TYPE (sym)) + if (POINTER_TYPE_P (TREE_TYPE (sym)) && nonnull_arg_p (sym)) set_value_range_to_nonnull (vr, TREE_TYPE (sym)); else @@ -2225,12 +2225,20 @@ extract_range_from_binary_expr (value_range_t *vr, else set_value_range_to_varying (&vr1); - /* If either range is UNDEFINED, so is the result. */ - if (vr0.type == VR_UNDEFINED || vr1.type == VR_UNDEFINED) + /* If both ranges are UNDEFINED, so is the result. */ + if (vr0.type == VR_UNDEFINED && vr1.type == VR_UNDEFINED) { set_value_range_to_undefined (vr); return; } + /* If one of the ranges is UNDEFINED drop it to VARYING for the following + code. At some point we may want to special-case operations that + have UNDEFINED result for all or some value-ranges of the not UNDEFINED + operand. */ + else if (vr0.type == VR_UNDEFINED) + set_value_range_to_varying (&vr0); + else if (vr1.type == VR_UNDEFINED) + set_value_range_to_varying (&vr1); /* The type of the resulting value range defaults to VR0.TYPE. */ type = vr0.type; @@ -6642,6 +6650,8 @@ vrp_visit_phi_node (gimple phi) if (vr_result.type == VR_VARYING) goto varying; + else if (vr_result.type == VR_UNDEFINED) + goto update_range; old_edges = vr_phi_edge_counts[SSA_NAME_VERSION (lhs)]; vr_phi_edge_counts[SSA_NAME_VERSION (lhs)] = edges; @@ -6713,6 +6723,7 @@ vrp_visit_phi_node (gimple phi) /* If the new range is different than the previous value, keep iterating. */ +update_range: if (update_value_range (lhs, &vr_result)) { if (dump_file && (dump_flags & TDF_DETAILS)) |