We can't use
void
test (long a, long b, long c, long d, long e)
{
...
__asm__ __volatile__ ("subq $8,%%rsp":::"cc");
ret = do_test_unaligned (a, b, c, d, e);
__asm__ __volatile__ ("addq $8,%%rsp":::"cc");
...
}
to call do_test_unaligned, which is marked with ms_abi attribute, with
an unaligned stack since GCC may save a function argument on stack and
retrieve it from stack to pass it to do_test_unaligned. When it happens,
stack adjustment in asm statements can lead to a random value in the
outgoing argument. Add an assembly function, call_do_test_unaligned, to
call do_test_unaligned with an unaligned stack.
PR testsuite/126927
* gcc.target/x86_64/abi/ms-sysv/do-test.S (call_do_test_unaligned):
New.
* gcc.target/x86_64/abi/ms-sysv/gen.cc (make_do_tests_decl):
Replace do_test_unaligned with call_do_test_unaligned.
(make_do_test): Remove asm statements with stack adjustment.
--
H.J.
From 8740c4f1bc7ecbcfc99f11225d7ca3f467b659fe Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <[email protected]>
Date: Tue, 18 Aug 2026 22:55:38 +0800
Subject: [PATCH] ms-sysv: Add call_do_test_unaligned
We can't use
void
test (long a, long b, long c, long d, long e)
{
...
__asm__ __volatile__ ("subq $8,%%rsp":::"cc");
ret = do_test_unaligned (a, b, c, d, e);
__asm__ __volatile__ ("addq $8,%%rsp":::"cc");
...
}
to call do_test_unaligned, which is marked with ms_abi attribute, with
an unaligned stack since GCC may save a function argument on stack and
retrieve it from stack to pass it to do_test_unaligned. When it happens,
stack adjustment in asm statements can lead to a random value in the
outgoing argument. Add an assembly function, call_do_test_unaligned, to
call do_test_unaligned with an unaligned stack.
PR testsuite/126927
* gcc.target/x86_64/abi/ms-sysv/do-test.S (call_do_test_unaligned):
New.
* gcc.target/x86_64/abi/ms-sysv/gen.cc (make_do_tests_decl):
Replace do_test_unaligned with call_do_test_unaligned.
(make_do_test): Remove asm statements with stack adjustment.
Signed-off-by: H.J. Lu <[email protected]>
---
.../gcc.target/x86_64/abi/ms-sysv/do-test.S | 14 ++++++++++++++
.../gcc.target/x86_64/abi/ms-sysv/gen.cc | 15 ++++-----------
2 files changed, 18 insertions(+), 11 deletions(-)
diff --git a/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/do-test.S b/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/do-test.S
index 9bc108b3e98..7432994bc95 100644
--- a/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/do-test.S
+++ b/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/do-test.S
@@ -105,6 +105,20 @@ FUNC_BEGIN(mem_to_regs)
retq
FUNC_END(mem_to_regs)
+FUNC_BEGIN(call_do_test_unaligned)
+ # Load the 5th argument to R10.
+ movq 0x28(%rsp), %r10
+ # Unalign stack.
+ subq $8, %rsp
+ # Push the 5th argument.
+ pushq %r10
+ subq $32, %rsp
+ call do_test_unaligned
+ addq $32, %rsp
+ addq $16, %rsp
+ ret
+FUNC_END(call_do_test_unaligned)
+
# NOTE: Not MT safe
FUNC_BEGIN(do_test_unaligned)
# The below alignment checks are to verify correctness of the test
diff --git a/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/gen.cc b/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/gen.cc
index 818a8875a6d..ceade25cd29 100644
--- a/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/gen.cc
+++ b/gcc/testsuite/gcc.target/x86_64/abi/ms-sysv/gen.cc
@@ -372,7 +372,7 @@ vector<class fn*> sysv_funcs;
vector<class fn*> msabi_funcs;
-/* Emit extern for do_test_aligned and do_test_unaligned (defined in do_test.S)
+/* Emit extern for do_test_aligned and call_do_test_unaligned (defined in do_test.S)
followed by all of the various do_test* function function pointers that
are just aliases of them. */
static void make_do_tests_decl (const vector<class arg> &args, ostream &out)
@@ -381,7 +381,7 @@ static void make_do_tests_decl (const vector<class arg> &args, ostream &out)
unsigned i, varargs, unaligned;
out << "extern __attribute__ ((ms_abi)) long do_test_aligned ();" << endl
- << "extern __attribute__ ((ms_abi)) long do_test_unaligned ();" << endl;
+ << "extern __attribute__ ((ms_abi)) long call_do_test_unaligned ();" << endl;
list_delimiter comma (", ");
for (i = extra_params_min; i <= args.size (); ++i)
@@ -402,7 +402,8 @@ static void make_do_tests_decl (const vector<class arg> &args, ostream &out)
<< ai->get_name ();
if (varargs)
out << comma.get () << "...";
- out << ") = (void*)do_test_" << (unaligned ? "un" : "")
+ out << ") = (void*)" << (unaligned ? "call_" : "")
+ << "do_test_" << (unaligned ? "un" : "")
<< "aligned;" << endl;
}
}
@@ -510,10 +511,6 @@ void make_do_test (const vector<class arg> &args,
out << ");" << endl;
/* End if init_test call. */
- if (f.get_realign () && unaligned == 1)
- out << " __asm__ __volatile__ (\"subq $8,%%rsp\":::\"cc\");"
- << endl;
-
out << " ret = do_test_"
<< (f.get_realign () && unaligned == 1 ? "u" : "")
<< (f.get_varargs () ? "v" : "")
@@ -524,10 +521,6 @@ void make_do_test (const vector<class arg> &args,
out << comma.get () << arg.get_name ();
out << ");" << endl;
- if (f.get_realign () && unaligned == 1)
- out << " __asm__ __volatile__ (\"addq $8,%%rsp\":::\"cc\");"
- << endl;
-
out << " check_results (ret);" << endl;
}
}
--
2.55.0
