On 26/08/16 10:40, Richard Biener wrote:
I suppose
you could get away with using sth entirely private to the backend,
like "sysv abi valist", also not ever user-creatable. Does this
side-step the FE issue?
It does.
Added comments and second test-case, as requested previously.
Bootstrapped and reg-tested on x86_64 -m64/-m32.
OK for trunk, 6 branch?
Thanks,
- Tom
Tag {ms,sysv}_va_list_type_node with '{ms,sysv}_abi va_list' attribute
2016-08-24 Tom de Vries <t...@codesourcery.com>
PR lto/70955
* config/i386/i386.c (ix86_build_builtin_va_list_64): Tag type with
'sysv_abi va_list' attribute.
(ix86_build_builtin_va_list): Tag type with 'ms_abi va_list' attribute.
(ix86_canonical_va_list_type): Handle 'sysv_abi/ms_abi va_list'
attributes.
* gcc.dg/pr70955.c: New test.
* gcc.dg/lto/pr70955_0.c: Same.
* gcc.dg/lto/pr70955_1.c: Same.
---
gcc/config/i386/i386.c | 109 +++++++++++++++--------------------
gcc/testsuite/gcc.dg/lto/pr70955_0.c | 13 +++++
gcc/testsuite/gcc.dg/lto/pr70955_1.c | 16 +++++
gcc/testsuite/gcc.dg/pr70955.c | 36 ++++++++++++
4 files changed, 111 insertions(+), 63 deletions(-)
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 2639c8c..792019b 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -10548,6 +10548,9 @@ ix86_build_builtin_va_list_64 (void)
layout_type (record);
+ TYPE_ATTRIBUTES (record) = tree_cons (get_identifier ("sysv_abi va_list"),
+ NULL_TREE, TYPE_ATTRIBUTES (record));
+
/* The correct type is an array type of one element. */
return build_array_type (record, build_index_type (size_zero_node));
}
@@ -10560,17 +10563,36 @@ ix86_build_builtin_va_list (void)
{
if (TARGET_64BIT)
{
- /* Initialize ABI specific va_list builtin types. */
- tree sysv_va_list, ms_va_list;
-
- sysv_va_list = ix86_build_builtin_va_list_64 ();
- sysv_va_list_type_node = build_variant_type_copy (sysv_va_list);
+ /* Initialize ABI specific va_list builtin types.
+
+ In lto1, we can encounter two va_list types:
+ - one as a result of the type-merge across TUs, and
+ - the one constructed here.
+ These two types will not have the same TYPE_MAIN_VARIANT, and therefore
+ a type identity check in canonical_va_list_type based on
+ TYPE_MAIN_VARIANT (which we used to have) will not work.
+ Instead, we tag each va_list_type_node with its unique attribute, and
+ look for the attribute in the type identity check in
+ canonical_va_list_type.
+
+ Tagging sysv_va_list_type_node directly with the attribute is
+ problematic since it's a array of one record, which will degrade into a
+ pointer to record when used as parameter (see build_va_arg comments for
+ an example), dropping the attribute in the process. So we tag the
+ record instead. */
+
+ /* For SYSV_ABI we use an array of one record. */
+ sysv_va_list_type_node = ix86_build_builtin_va_list_64 ();
/* For MS_ABI we use plain pointer to argument area. */
- ms_va_list = build_pointer_type (char_type_node);
- ms_va_list_type_node = build_variant_type_copy (ms_va_list);
+ tree char_ptr_type = build_pointer_type (char_type_node);
+ tree attr = tree_cons (get_identifier ("ms_abi va_list"), NULL_TREE,
+ TYPE_ATTRIBUTES (char_ptr_type));
+ ms_va_list_type_node = build_type_attribute_variant (char_ptr_type, attr);
- return (ix86_abi == MS_ABI) ? ms_va_list : sysv_va_list;
+ return ((ix86_abi == MS_ABI)
+ ? ms_va_list_type_node
+ : sysv_va_list_type_node);
}
else
{
@@ -44669,6 +44691,8 @@ static const struct attribute_spec ix86_attribute_table[] =
/* ms_abi and sysv_abi calling convention function attributes. */
{ "ms_abi", 0, 0, false, true, true, ix86_handle_abi_attribute, true },
{ "sysv_abi", 0, 0, false, true, true, ix86_handle_abi_attribute, true },
+ { "ms_abi va_list", 0, 0, false, false, false, NULL, false },
+ { "sysv_abi va_list", 0, 0, false, false, false, NULL, false },
{ "ms_hook_prologue", 0, 0, true, false, false, ix86_handle_fndecl_attribute,
false },
{ "callee_pop_aggregate_return", 1, 1, false, true, true,
@@ -48563,8 +48587,6 @@ ix86_fn_abi_va_list (tree fndecl)
static tree
ix86_canonical_va_list_type (tree type)
{
- tree wtype, htype;
-
/* Resolve references and pointers to va_list type. */
if (TREE_CODE (type) == MEM_REF)
type = TREE_TYPE (type);
@@ -48573,64 +48595,25 @@ ix86_canonical_va_list_type (tree type)
else if (POINTER_TYPE_P (type) && TREE_CODE (TREE_TYPE (type)) == ARRAY_TYPE)
type = TREE_TYPE (type);
- if (TARGET_64BIT && va_list_type_node != NULL_TREE)
+ if (TARGET_64BIT)
{
- wtype = va_list_type_node;
- gcc_assert (wtype != NULL_TREE);
- htype = type;
- if (TREE_CODE (wtype) == ARRAY_TYPE)
- {
- /* If va_list is an array type, the argument may have decayed
- to a pointer type, e.g. by being passed to another function.
- In that case, unwrap both types so that we can compare the
- underlying records. */
- if (TREE_CODE (htype) == ARRAY_TYPE
- || POINTER_TYPE_P (htype))
- {
- wtype = TREE_TYPE (wtype);
- htype = TREE_TYPE (htype);
- }
- }
- if (TYPE_MAIN_VARIANT (wtype) == TYPE_MAIN_VARIANT (htype))
- return va_list_type_node;
- wtype = sysv_va_list_type_node;
- gcc_assert (wtype != NULL_TREE);
- htype = type;
- if (TREE_CODE (wtype) == ARRAY_TYPE)
- {
- /* If va_list is an array type, the argument may have decayed
- to a pointer type, e.g. by being passed to another function.
- In that case, unwrap both types so that we can compare the
- underlying records. */
- if (TREE_CODE (htype) == ARRAY_TYPE
- || POINTER_TYPE_P (htype))
- {
- wtype = TREE_TYPE (wtype);
- htype = TREE_TYPE (htype);
- }
- }
- if (TYPE_MAIN_VARIANT (wtype) == TYPE_MAIN_VARIANT (htype))
- return sysv_va_list_type_node;
- wtype = ms_va_list_type_node;
- gcc_assert (wtype != NULL_TREE);
- htype = type;
- if (TREE_CODE (wtype) == ARRAY_TYPE)
+ if (lookup_attribute ("ms_abi va_list", TYPE_ATTRIBUTES (type)))
+ return ms_va_list_type_node;
+
+ if ((TREE_CODE (type) == ARRAY_TYPE
+ && integer_zerop (array_type_nelts (type)))
+ || POINTER_TYPE_P (type))
{
- /* If va_list is an array type, the argument may have decayed
- to a pointer type, e.g. by being passed to another function.
- In that case, unwrap both types so that we can compare the
- underlying records. */
- if (TREE_CODE (htype) == ARRAY_TYPE
- || POINTER_TYPE_P (htype))
- {
- wtype = TREE_TYPE (wtype);
- htype = TREE_TYPE (htype);
- }
+ tree elem_type = TREE_TYPE (type);
+ if (TREE_CODE (elem_type) == RECORD_TYPE
+ && lookup_attribute ("sysv_abi va_list",
+ TYPE_ATTRIBUTES (elem_type)))
+ return sysv_va_list_type_node;
}
- if (TYPE_MAIN_VARIANT (wtype) == TYPE_MAIN_VARIANT (htype))
- return ms_va_list_type_node;
+
return NULL_TREE;
}
+
return std_canonical_va_list_type (type);
}
diff --git a/gcc/testsuite/gcc.dg/lto/pr70955_0.c b/gcc/testsuite/gcc.dg/lto/pr70955_0.c
new file mode 100644
index 0000000..c3b75fc
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/lto/pr70955_0.c
@@ -0,0 +1,13 @@
+/* __builtin_ms_va_list is only supported for x86_64 -m64. */
+/* { dg-skip-if "" { ! {x86_64-*-* && { ! ilp32 } } } } */
+
+#include <stdio.h>
+
+int __attribute__((ms_abi)) va_demo (int count, ...);
+
+int
+main (void)
+{
+ printf ("sum == %d\n", va_demo (5, 1, 2, 3, 4, 5));
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/lto/pr70955_1.c b/gcc/testsuite/gcc.dg/lto/pr70955_1.c
new file mode 100644
index 0000000..204c28b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/lto/pr70955_1.c
@@ -0,0 +1,16 @@
+int __attribute__((ms_abi))
+va_demo (int count, ...)
+{
+ int sum = 0;
+ __builtin_ms_va_list ap;
+
+ __builtin_ms_va_start (ap, count);
+ while (count)
+ {
+ sum += __builtin_va_arg (ap, int);
+ --count;
+ }
+
+ __builtin_ms_va_end (ap);
+ return sum;
+}
diff --git a/gcc/testsuite/gcc.dg/pr70955.c b/gcc/testsuite/gcc.dg/pr70955.c
new file mode 100644
index 0000000..1275a5f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr70955.c
@@ -0,0 +1,36 @@
+/* __builtin_ms_va_list is only supported for x86_64 -m64. */
+/* { dg-do run { target { x86_64-*-* && { ! ilp32 } } } } */
+/* { dg-require-effective-target lto } */
+/* { dg-options "-flto" } */
+
+#include <stdio.h>
+
+int __attribute__((ms_abi))
+foo (int n, ...)
+{
+ __builtin_ms_va_list ap;
+ int sum = 0;
+
+ __builtin_ms_va_start (ap, n);
+
+ while (n--)
+ {
+ sum += __builtin_va_arg (ap, int);
+ printf ("sum = %d\n", sum);
+ }
+
+ __builtin_ms_va_end (ap);
+
+ return sum;
+}
+
+int
+main (void)
+{
+ int res = foo (10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+
+ if (res != 55)
+ __builtin_abort ();
+
+ return 0;
+}
