Hi,
On Thu, Mar 16, 2017 at 05:57:51PM +0100, Martin Jambor wrote:
> Hi,
>
> On Mon, Mar 13, 2017 at 01:46:47PM +0100, Richard Biener wrote:
> > On Fri, 10 Mar 2017, Martin Jambor wrote:
> >
> > > Hi,
> > >
> > > PR 77333 is a i686-windows target bug, which however has its root in
> > > our general mechanism of adjusting gimple statements when redirecting
> > > call graph edge. Basically, these three things trigger it:
> > >
> > > 1) IPA-CP figures out that the this parameter of a C++ class method is
> > > unused and because the class is in an anonymous namespace, it can
> > > be removed and all calls adjusted. That effectively changes a
> > > normal method into a static method and so internally, its type
> > > changes from METHOD_TYPE to FUNCTION_TYPE.
> > >
> > > 2) Since the fix of PR 57330, we do not update gimple_call_fntype to
> > > match the new type, in fact we explicitely set it to the old, now
> > > invalid, type (see redirect_call_stmt_to_callee in cgraph.c).
> > >
> > > 3) Function ix86_get_callcvt which decides on call ABI, ends with the
> > > following condition:
> > >
> > > if (ret != 0
> > > || is_stdarg
> > > || TREE_CODE (type) != METHOD_TYPE
> > > || ix86_function_type_abi (type) != MS_ABI)
> > > return IX86_CALLCVT_CDECL | ret;
> > >
> > > return IX86_CALLCVT_THISCALL;
> > >
> > > ...and since now the callee is no longer a METHOD_TYPE but callers
> > > still think that they are, leading to calling convention mismatches
> > > and subsequent crashes. It took me quite a lot of time to come up
> > > with a small testcase (reproducible using wine) but eventually I
> > > managed.
> > >
> > > The fix is not to do 2) above, but doing so without re-introducing PR
> > > 57330, of course.
...
> >
> > In general I am sympathetic with not doing any IPA propagation
> > across call stmt signature incompatibilties. Of course we may
> > be still too strict in those compatibility check...
> >
> > > So the alternative would be to re-check when doing the gimple
> > > statement adjustment and if the types match, then set the correct new
> > > gimple_fntype and if they don't... then we can either leave it be or
> > > just run the same type transformation on it as we did on the callee,
> > > though they would be bogus either way. That is implemented in the
> > > attached patch.
> >
...
> After talking to Honza today, we decided to probably go this route and
> use the patch doing the type conversion at acall-sites when necessary.
> Honza promised to review the patch soon (he wants to figure out why
> former_clone_of can be NULL, something I decided not to bother about
> since at that time I thought the other approach was going to be
> preferable).
>
and this is a slightly adjusted patch that is a result of what we
talked about. I know that it is potentially disruptive change, so I
have tested it with:
- bootstrap and testing and LTO-bootstrap and testing on x86_64-linux,
- bootstrap and testing on i686-linux, ppc64le-linux and ia64-linux
- bootstrap on aarch64-linux (no testing because there is no dejagnu
installed on gcc117.fsffrance.org),
- testing on i686-w64-mingw32 on Linux+wine, and
- testing on powerpc-aix is underway.
OK for trunk (and subsequently to backport to gcc 6 and 5)?
Thanks,
Martin
2017-03-24 Martin Jambor <mjam...@suse.cz>
PR ipa/77333
* cgraph.h (cgraph_build_function_type_skip_args): Declare.
* cgraph.c (redirect_call_stmt_to_callee): Set gimple fntype so that
it reflects the signature changes performed at the callee side.
* cgraphclones.c (build_function_type_skip_args): Make public, renamed
to cgraph_build_function_type_skip_args.
(build_function_decl_skip_args): Adjust call to the above function.
testsuite/
* g++.dg/ipa/pr77333.C: New test.
---
gcc/cgraph.c | 17 +++++++++-
gcc/cgraph.h | 2 ++
gcc/cgraphclones.c | 9 +++---
gcc/testsuite/g++.dg/ipa/pr77333.C | 65 ++++++++++++++++++++++++++++++++++++++
4 files changed, 88 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/ipa/pr77333.C
diff --git a/gcc/cgraph.c b/gcc/cgraph.c
index 839388496ee..92ae0910c60 100644
--- a/gcc/cgraph.c
+++ b/gcc/cgraph.c
@@ -1424,8 +1424,23 @@ cgraph_edge::redirect_call_stmt_to_callee (void)
if (skip_bounds)
new_stmt = chkp_copy_call_skip_bounds (new_stmt);
+ tree old_fntype = gimple_call_fntype (e->call_stmt);
gimple_call_set_fndecl (new_stmt, e->callee->decl);
- gimple_call_set_fntype (new_stmt, gimple_call_fntype (e->call_stmt));
+ cgraph_node *origin = e->callee;
+ while (origin->clone_of)
+ origin = origin->clone_of;
+
+ if ((origin->former_clone_of
+ && old_fntype == TREE_TYPE (origin->former_clone_of))
+ || old_fntype == TREE_TYPE (origin->decl))
+ gimple_call_set_fntype (new_stmt, TREE_TYPE (e->callee->decl));
+ else
+ {
+ bitmap skip = e->callee->clone.combined_args_to_skip;
+ tree t = cgraph_build_function_type_skip_args (old_fntype, skip,
+ false);
+ gimple_call_set_fntype (new_stmt, t);
+ }
if (gimple_vdef (new_stmt)
&& TREE_CODE (gimple_vdef (new_stmt)) == SSA_NAME)
diff --git a/gcc/cgraph.h b/gcc/cgraph.h
index 3889a3e1701..62cebd9e55a 100644
--- a/gcc/cgraph.h
+++ b/gcc/cgraph.h
@@ -2326,6 +2326,8 @@ void tree_function_versioning (tree, tree,
vec<ipa_replace_map *, va_gc> *,
void dump_callgraph_transformation (const cgraph_node *original,
const cgraph_node *clone,
const char *suffix);
+tree cgraph_build_function_type_skip_args (tree orig_type, bitmap args_to_skip,
+ bool skip_return);
/* In cgraphbuild.c */
int compute_call_stmt_bb_frequency (tree, basic_block bb);
diff --git a/gcc/cgraphclones.c b/gcc/cgraphclones.c
index c2337e84553..69572b926c4 100644
--- a/gcc/cgraphclones.c
+++ b/gcc/cgraphclones.c
@@ -152,9 +152,9 @@ cgraph_edge::clone (cgraph_node *n, gcall *call_stmt,
unsigned stmt_uid,
/* Build variant of function type ORIG_TYPE skipping ARGS_TO_SKIP and the
return value if SKIP_RETURN is true. */
-static tree
-build_function_type_skip_args (tree orig_type, bitmap args_to_skip,
- bool skip_return)
+tree
+cgraph_build_function_type_skip_args (tree orig_type, bitmap args_to_skip,
+ bool skip_return)
{
tree new_type = NULL;
tree args, new_args = NULL;
@@ -219,7 +219,8 @@ build_function_decl_skip_args (tree orig_decl, bitmap
args_to_skip,
if (prototype_p (new_type)
|| (skip_return && !VOID_TYPE_P (TREE_TYPE (new_type))))
new_type
- = build_function_type_skip_args (new_type, args_to_skip, skip_return);
+ = cgraph_build_function_type_skip_args (new_type, args_to_skip,
+ skip_return);
TREE_TYPE (new_decl) = new_type;
/* For declarations setting DECL_VINDEX (i.e. methods)
diff --git a/gcc/testsuite/g++.dg/ipa/pr77333.C
b/gcc/testsuite/g++.dg/ipa/pr77333.C
new file mode 100644
index 00000000000..1ef997f7a54
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ipa/pr77333.C
@@ -0,0 +1,65 @@
+// { dg-do run }
+// { dg-options "-O2 -fno-ipa-sra" }
+
+volatile int global;
+int __attribute__((noinline, noclone))
+get_data (int i)
+{
+ global = i;
+ return i;
+}
+
+typedef int array[32];
+
+namespace {
+
+char buf[512];
+
+class A
+{
+public:
+ int field;
+ char *s;
+
+ A() : field(223344)
+ {
+ s = buf;
+ }
+
+ int __attribute__((noinline))
+ foo (int a, int b, int c, int d, int e, int f, int g, int h, int i, int j,
+ int k, int l, int m, int n, int o, int p, int q, int r, int s, int t)
+ {
+ global = a+b+c+d+e+f+g+h+i+j+k+l+m+n+o+p+q+r+s+t;
+ return global;
+ }
+
+ int __attribute__((noinline))
+ bar()
+ {
+ int r = foo (get_data (1), get_data (1), get_data (1), get_data (1),
+ get_data (1), get_data (1), get_data (1), get_data (1),
+ get_data (1), get_data (1), get_data (1), get_data (1),
+ get_data (1), get_data (1), get_data (1), get_data (1),
+ get_data (1), get_data (1), get_data (1), get_data (1));
+
+ if (field != 223344)
+ __builtin_abort ();
+ return 0;
+ }
+};
+
+}
+
+int main (int argc, char **argv)
+{
+ A a;
+ int r = a.bar();
+ r = a.bar ();
+ if (a.field != 223344)
+ __builtin_abort ();
+ if (global != 20)
+ __builtin_abort ();
+
+ return r;
+}
--
2.12.0
