Hi Martin,
On 07/12/16 21:08, Martin Jambor wrote:
Hello Kugan,
sorry, I have lost track of this patch and re-discovered it only now.
On Mon, Nov 28, 2016 at 04:25:00PM +1100, kugan wrote:
Hi,
On 24/11/16 19:48, Richard Biener wrote:
On Wed, Nov 23, 2016 at 4:33 PM, Martin Jambor <mjam...@suse.cz> wrote:
Hi,
On Fri, Nov 18, 2016 at 12:38:18PM +1100, kugan wrote:
Hi,
I was relying on ipa_get_callee_param_type to get type of parameter and then
convert arguments to this type while computing jump functions. However, in
cases like shown in PR78365, ipa_get_callee_param_type, instead of giving
up, would return the wrong type.
At what stage does this happen? During analysis
(ipa_compute_jump_functions_for_edge) or at WPA
(propagate_constants_accross_call)? Both?
Hmm, where does jump function compute require the callee type?
In my view the jump function should record
(expected-incoming-type) arg [OP X]
for each call argument in its body. Thus required conversions are
done at WPA propagation time.
I think the current uses of
ipa_get_callee_param_type are fine with this.
Attached patch now uses callee's DECL_ARGUMENTS to get the type. If it
cannot be found, then I would give up and set the jump function to varying.
But DECL_ARGUMENTS is not available at WPA stage with LTO so your
patch would make our IPA layer to optimize less with LTO. This was
the reason to go through the hoops of TYPE_ARG_TYPES in the first
place.
If TYPE_ARG_TYPES cannot be trusted, then I'm afraid we are back to
square one and indeed need to put the correct type in jump functions.
If DECL_ARGUMENTS is not available at WPA stage then I see no other
way than to put the types on the jump functions.
Here is a patch that does this. To fox PR78365, in
ipa_get_callee_param_type, I am now checking DECL_ARGUMENTS first. I lto
bootstrapped and regression tested on x86_64-linux-gnu and ppc64le-linux
with no new regressions. I will build Firefox and measure the memory usage
as Honza suggested based on the feedback.
So, do you have any numbers?
I will do it. How do you measure the gcc's memory usage while building
Firefox. I saw Honza's LTO blog talks about using vmstat result. Any
tips please?
diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index 2ec671f..3d50041 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -1846,11 +1846,11 @@ propagate_bits_accross_jump_function (cgraph_edge *cs,
int idx, ipa_jump_func *j
static bool
propagate_vr_accross_jump_function (cgraph_edge *cs,
ipa_jump_func *jfunc,
- struct ipcp_param_lattices *dest_plats,
- tree param_type)
+ struct ipcp_param_lattices *dest_plats)
{
struct ipcp_param_lattices *src_lats;
ipcp_vr_lattice *dest_lat = &dest_plats->m_value_range;
+ tree param_type = jfunc->param_type;
if (dest_lat->bottom_p ())
return false;
@@ -1895,9 +1895,9 @@ propagate_vr_accross_jump_function (cgraph_edge *cs,
tree val = ipa_get_jf_constant (jfunc);
if (TREE_CODE (val) == INTEGER_CST)
{
+ val = fold_convert (param_type, val);
if (TREE_OVERFLOW_P (val))
val = drop_tree_overflow (val);
- val = fold_convert (param_type, val);
jfunc->vr_known = true;
jfunc->m_vr.type = VR_RANGE;
jfunc->m_vr.min = val;
@@ -2247,7 +2247,6 @@ propagate_constants_accross_call (struct cgraph_edge *cs)
{
struct ipa_jump_func *jump_func = ipa_get_ith_jump_func (args, i);
struct ipcp_param_lattices *dest_plats;
- tree param_type = ipa_get_callee_param_type (cs, i);
dest_plats = ipa_get_parm_lattices (callee_info, i);
if (availability == AVAIL_INTERPOSABLE)
@@ -2264,8 +2263,7 @@ propagate_constants_accross_call (struct cgraph_edge *cs)
dest_plats);
if (opt_for_fn (callee->decl, flag_ipa_vrp))
ret |= propagate_vr_accross_jump_function (cs,
- jump_func, dest_plats,
- param_type);
+ jump_func, dest_plats);
else
ret |= dest_plats->m_value_range.set_to_bottom ();
}
diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index 90c19fc..235531b 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -1651,14 +1651,24 @@ determine_locally_known_aggregate_parts (gcall *call,
tree arg,
/* Return the Ith param type of callee associated with call graph
edge E. */
-tree
+static tree
ipa_get_callee_param_type (struct cgraph_edge *e, int i)
{
int n;
+ tree t = e->callee ? DECL_ARGUMENTS (e->callee->decl) : NULL_TREE;
+ if (t)
+ for (n = 0; n < i; n++)
+ {
+ if (!t)
+ return NULL;
+ t = TREE_CHAIN (t);
+ }
+ if (t)
+ return TREE_TYPE (t);
tree type = (e->callee
? TREE_TYPE (e->callee->decl)
: gimple_call_fntype (e->call_stmt));
- tree t = TYPE_ARG_TYPES (type);
+ t = TYPE_ARG_TYPES (type);
If TYPE_ARG_TYPES is inherently unreliable then I am afraid you must
not fallback on it but rather return NULL if cs->callee is not
available and adjust the caller to give up in that case.
(I have checked both testcases that we hope to fix with types in jump
functions and the gimple_call_fntype is the same as
TREE_TYPE(e->callee->decl) so that does not help either).
Do you like the attached patch where I have removed it.
for (n = 0; n < i; n++)
{
@@ -1670,15 +1680,6 @@ ipa_get_callee_param_type (struct cgraph_edge *e, int i)
return TREE_VALUE (t);
if (!e->callee)
return NULL;
- t = DECL_ARGUMENTS (e->callee->decl);
- for (n = 0; n < i; n++)
- {
- if (!t)
- return NULL;
- t = TREE_CHAIN (t);
- }
- if (t)
- return TREE_TYPE (t);
return NULL;
}
@@ -1724,6 +1725,7 @@ ipa_compute_jump_functions_for_edge (struct
ipa_func_body_info *fbi,
useful_context = true;
}
+ jfunc->param_type = param_type;
if (POINTER_TYPE_P (TREE_TYPE (arg)))
{
bool addr_nonzero = false;
@@ -4709,6 +4711,7 @@ ipa_write_jump_function (struct output_block *ob,
int i, count;
streamer_write_uhwi (ob, jump_func->type);
+ stream_write_tree (ob, jump_func->param_type, true);
switch (jump_func->type)
{
case IPA_JF_UNKNOWN:
@@ -4792,6 +4795,7 @@ ipa_read_jump_function (struct lto_input_block *ib,
int i, count;
jftype = (enum jump_func_type) streamer_read_uhwi (ib);
+ jump_func->param_type = stream_read_tree (ib, data_in);
switch (jftype)
{
case IPA_JF_UNKNOWN:
diff --git a/gcc/ipa-prop.h b/gcc/ipa-prop.h
index 0e75cf4..8dcce99 100644
--- a/gcc/ipa-prop.h
+++ b/gcc/ipa-prop.h
@@ -180,6 +180,7 @@ struct GTY (()) ipa_jump_func
/* Information about value range. */
bool vr_known;
+ tree param_type;
Please add a comment describing what this is.
Done. LTO bootstrapped and regression tested on x86_64-linux-gnu with
https://gcc.gnu.org/ml/gcc-patches/2016-12/msg00716.html and there is no
new regressions.
Is this OK?
Thanks,
Kugan
Otherwise, the intent looks fine to me.
Thanks!
Martin
diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index 2ec671f..9853467 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -1846,11 +1846,11 @@ propagate_bits_accross_jump_function (cgraph_edge *cs,
int idx, ipa_jump_func *j
static bool
propagate_vr_accross_jump_function (cgraph_edge *cs,
ipa_jump_func *jfunc,
- struct ipcp_param_lattices *dest_plats,
- tree param_type)
+ struct ipcp_param_lattices *dest_plats)
{
struct ipcp_param_lattices *src_lats;
ipcp_vr_lattice *dest_lat = &dest_plats->m_value_range;
+ tree param_type = jfunc->param_type;
if (dest_lat->bottom_p ())
return false;
@@ -2247,7 +2247,6 @@ propagate_constants_accross_call (struct cgraph_edge *cs)
{
struct ipa_jump_func *jump_func = ipa_get_ith_jump_func (args, i);
struct ipcp_param_lattices *dest_plats;
- tree param_type = ipa_get_callee_param_type (cs, i);
dest_plats = ipa_get_parm_lattices (callee_info, i);
if (availability == AVAIL_INTERPOSABLE)
@@ -2264,8 +2263,7 @@ propagate_constants_accross_call (struct cgraph_edge *cs)
dest_plats);
if (opt_for_fn (callee->decl, flag_ipa_vrp))
ret |= propagate_vr_accross_jump_function (cs,
- jump_func, dest_plats,
- param_type);
+ jump_func, dest_plats);
else
ret |= dest_plats->m_value_range.set_to_bottom ();
}
diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index 642111d..21ee251 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -1659,26 +1659,13 @@ determine_locally_known_aggregate_parts (gcall *call,
tree arg,
/* Return the Ith param type of callee associated with call graph
edge E. */
-tree
+static tree
ipa_get_callee_param_type (struct cgraph_edge *e, int i)
{
int n;
- tree type = (e->callee
- ? TREE_TYPE (e->callee->decl)
- : gimple_call_fntype (e->call_stmt));
- tree t = TYPE_ARG_TYPES (type);
-
- for (n = 0; n < i; n++)
- {
- if (!t)
- break;
- t = TREE_CHAIN (t);
- }
- if (t)
- return TREE_VALUE (t);
if (!e->callee)
- return NULL;
- t = DECL_ARGUMENTS (e->callee->decl);
+ return NULL;
+ tree t = DECL_ARGUMENTS (e->callee->decl);
for (n = 0; n < i; n++)
{
if (!t)
@@ -1732,6 +1719,7 @@ ipa_compute_jump_functions_for_edge (struct
ipa_func_body_info *fbi,
useful_context = true;
}
+ jfunc->param_type = param_type;
if (POINTER_TYPE_P (TREE_TYPE (arg)))
{
bool addr_nonzero = false;
@@ -4717,6 +4705,7 @@ ipa_write_jump_function (struct output_block *ob,
int i, count;
streamer_write_uhwi (ob, jump_func->type);
+ stream_write_tree (ob, jump_func->param_type, true);
switch (jump_func->type)
{
case IPA_JF_UNKNOWN:
@@ -4800,6 +4789,7 @@ ipa_read_jump_function (struct lto_input_block *ib,
int i, count;
jftype = (enum jump_func_type) streamer_read_uhwi (ib);
+ jump_func->param_type = stream_read_tree (ib, data_in);
switch (jftype)
{
case IPA_JF_UNKNOWN:
diff --git a/gcc/ipa-prop.h b/gcc/ipa-prop.h
index 0e75cf4..eeb0f6b 100644
--- a/gcc/ipa-prop.h
+++ b/gcc/ipa-prop.h
@@ -182,6 +182,9 @@ struct GTY (()) ipa_jump_func
bool vr_known;
value_range m_vr;
+ /* Type of callee param corresponding to this jump_func. */
+ tree param_type;
+
enum jump_func_type type;
/* Represents a value of a jump function. pass_through is used only in jump
function context. constant represents the actual constant in constant
jump
@@ -818,7 +821,6 @@ ipa_parm_adjustment *ipa_get_adjustment_candidate (tree **,
bool *,
ipa_parm_adjustment_vec,
bool);
void ipa_release_body_info (struct ipa_func_body_info *);
-tree ipa_get_callee_param_type (struct cgraph_edge *e, int i);
/* From tree-sra.c: */
tree build_ref_for_offset (location_t, tree, HOST_WIDE_INT, bool, tree,
diff --git a/gcc/testsuite/gcc.dg/torture/pr78365.c
b/gcc/testsuite/gcc.dg/torture/pr78365.c
index e69de29..5180a01 100644
--- a/gcc/testsuite/gcc.dg/torture/pr78365.c
+++ b/gcc/testsuite/gcc.dg/torture/pr78365.c
@@ -0,0 +1,21 @@
+/* { dg-do compile } */
+
+int a, b, c;
+char d;
+static void fn1 (void *, int);
+int fn2 (int);
+
+void fn1 (cc, yh) void *cc;
+char yh;
+{
+ char y;
+ a = fn2(c - b + 1);
+ for (; y <= yh; y++)
+ ;
+}
+
+void fn3()
+{
+ fn1((void *)fn3, 1);
+ fn1((void *)fn3, d - 1);
+}
