From: H.J. Lu <hjl.tools@gmail.com>
Date: Tue, 31 Mar 2026 15:59:50 +0000 (-0700)
Subject: Check BIGGEST_ALIGNMENT when forcing a local copy
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=cc33cf487524e738e3bb723154ce315dda4fefdd;p=thirdparty%2Fgcc.git

Check BIGGEST_ALIGNMENT when forcing a local copy

BIGGEST_ALIGNMENT is the biggest alignment that any data type can require
on the target machine.  It is not the biggest alignment that is supported,
just the biggest alignment that, when violated, may cause a fault.

MAX_SUPPORTED_STACK_ALIGNMENT is the maximum stack alignment guaranteed by
the backend.  If SUPPORTS_STACK_ALIGNMENT is false, it is defined as
PREFERRED_STACK_BOUNDARY.

Adjust alignment check forcing a local copy if the argument on stack is
not aligned to its type and the current alignment is less than the
minimum of BIGGEST_ALIGNMENT and MAX_SUPPORTED_STACK_ALIGNMENT.

gcc/

	PR middle-end/124697
	* function.cc (assign_parm_adjust_stack_rtl): Force a local copy
	if the current alignment is less than the minimum of
	BIGGEST_ALIGNMENT and MAX_SUPPORTED_STACK_ALIGNMENT.

gcc/testsuite/

	PR middle-end/124697
	* gcc.target/i386/pr120839-1b.c: Adjusted.
	* gcc.target/i386/pr124697-1a.c: New test.
	* gcc.target/i386/pr124697-1b.c: Likewise.
	* gcc.target/i386/pr124697-2a.c: Likewise.
	* gcc.target/i386/pr124697-2b.c: Likewise.
	* gcc.target/i386/pr124697-3a.c: Likewise.
	* gcc.target/i386/pr124697-3b.c: Likewise.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
---

diff --git a/gcc/function.cc b/gcc/function.cc
index 46c0d8b54c2..109821c16fc 100644
--- a/gcc/function.cc
+++ b/gcc/function.cc
@@ -2840,7 +2840,8 @@ assign_parm_adjust_stack_rtl (tree parm, struct assign_parm_data_one *data)
 						 MEM_ALIGN (stack_parm))))
 	  || (data->nominal_type
 	      && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
-	      && (MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY
+	      && ((MEM_ALIGN (stack_parm)
+		   < MIN (BIGGEST_ALIGNMENT, MAX_SUPPORTED_STACK_ALIGNMENT))
 		  /* If its address is taken, make a local copy whose
 		     maximum alignment is MAX_SUPPORTED_STACK_ALIGNMENT.
 		   */
diff --git a/gcc/testsuite/gcc.target/i386/pr120839-1b.c b/gcc/testsuite/gcc.target/i386/pr120839-1b.c
index d9dafc19afb..cd7701f1d89 100644
--- a/gcc/testsuite/gcc.target/i386/pr120839-1b.c
+++ b/gcc/testsuite/gcc.target/i386/pr120839-1b.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
 /* { dg-options "-O2 -mavx2" } */
-/* { dg-final { scan-assembler-not "and\[lq\]?\[\\t \]*\\$-32,\[\\t \]*%\[re\]?sp" { xfail ia32 } } } */
+/* { dg-final { scan-assembler "and\[lq\]?\[\\t \]*\\$-32,\[\\t \]*%\[re\]?sp" } } */
 
 #include "pr120839-1a.c"
diff --git a/gcc/testsuite/gcc.target/i386/pr124697-1a.c b/gcc/testsuite/gcc.target/i386/pr124697-1a.c
new file mode 100644
index 00000000000..63d5cc7862c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr124697-1a.c
@@ -0,0 +1,31 @@
+/* { dg-do run  { target avx2_runtime } }  */
+/* { dg-options "-O2 -mavx2" } */
+
+typedef double v4df __attribute__((vector_size(32)));
+typedef double v2df __attribute__((vector_size(16)));
+typedef struct {
+  v2df a[2];
+} c __attribute__((aligned(32)));
+v4df d;
+c v;
+
+__attribute__ ((noipa))
+void
+foo (float a1, float a2, float a3, float a4, float a5, float a6, c f)
+{
+  d = *(v4df *) &f;
+}
+
+__attribute__ ((noipa))
+void
+bar (void)
+{
+  foo (0, 0, 0, 0, 0, 0, v);
+}
+
+int
+main ()
+{
+  bar ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr124697-1b.c b/gcc/testsuite/gcc.target/i386/pr124697-1b.c
new file mode 100644
index 00000000000..3b74f62b508
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr124697-1b.c
@@ -0,0 +1,19 @@
+/* { dg-do compile }  */
+/* { dg-options "-O2 -mno-avx512f -mavx2" } */
+/* { dg-final { scan-assembler-times "vmovupd.*, %ymm0" 1 } } */
+/* { dg-final { scan-assembler "and\[lq\]?\[\\t \]*\\$-32,\[\\t \]*%\[re\]?sp" } } */
+/* { dg-final { scan-assembler-not "vmovapd.*, %ymm0" } } */
+
+typedef double v4df __attribute__((vector_size(32)));
+typedef double v2df __attribute__((vector_size(16)));
+typedef struct {
+  v2df a[2];
+} c __attribute__((aligned(32)));
+v4df d;
+c v;
+
+void
+foo (float a1, float a2, float a3, float a4, float a5, float a6, c f)
+{
+  d = *(v4df *) &f;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr124697-2a.c b/gcc/testsuite/gcc.target/i386/pr124697-2a.c
new file mode 100644
index 00000000000..46a1f953290
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr124697-2a.c
@@ -0,0 +1,30 @@
+/* { dg-do run  { target avx2_runtime } }  */
+/* { dg-options "-O2 -mavx2" } */
+
+typedef double v4df __attribute__((vector_size(32)));
+typedef struct {
+  v4df a[2];
+} c __attribute__((aligned(64)));
+v4df d;
+c v;
+
+__attribute__ ((noipa))
+void
+foo (float a1, float a2, float a3, float a4, float a5, float a6, c f)
+{
+  d = *(v4df *) &f;
+}
+
+__attribute__ ((noipa))
+void
+bar (void)
+{
+  foo (0, 0, 0, 0, 0, 0, v);
+}
+
+int
+main ()
+{
+  bar ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr124697-2b.c b/gcc/testsuite/gcc.target/i386/pr124697-2b.c
new file mode 100644
index 00000000000..1c2256df9b9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr124697-2b.c
@@ -0,0 +1,18 @@
+/* { dg-do compile }  */
+/* { dg-options "-O2 -mno-avx512f -mavx2" } */
+/* { dg-final { scan-assembler-times "vmovapd.*, %ymm0" 1 } } */
+/* { dg-final { scan-assembler-not "vmovupd.*, %ymm0" } } */
+/* { dg-final { scan-assembler-not "and\[lq\]?\[\\t \]*\\$-64,\[\\t \]*%\[re\]?sp" } } */
+
+typedef double v4df __attribute__((vector_size(32)));
+typedef struct {
+  v4df a[2];
+} c __attribute__((aligned(64)));
+v4df d;
+c v;
+
+void
+foo (float a1, float a2, float a3, float a4, float a5, float a6, c f)
+{
+  d = *(v4df *) &f;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr124697-3a.c b/gcc/testsuite/gcc.target/i386/pr124697-3a.c
new file mode 100644
index 00000000000..87e6f6f7520
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr124697-3a.c
@@ -0,0 +1,31 @@
+/* { dg-do run  { target avx512f_runtime } }  */
+/* { dg-options "-O2 -mavx512f" } */
+
+typedef double v4df __attribute__((vector_size(32)));
+typedef double v8df __attribute__((vector_size(64)));
+typedef struct {
+  v4df a[2];
+} c __attribute__((aligned(64)));
+v8df d;
+c v;
+
+__attribute__ ((noipa))
+void
+foo (float a1, float a2, float a3, float a4, float a5, float a6, c f)
+{
+  d = *(v8df *) &f;
+}
+
+__attribute__ ((noipa))
+void
+bar (void)
+{
+  foo (0, 0, 0, 0, 0, 0, v);
+}
+
+int
+main ()
+{
+  bar ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr124697-3b.c b/gcc/testsuite/gcc.target/i386/pr124697-3b.c
new file mode 100644
index 00000000000..31d52f83ad5
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr124697-3b.c
@@ -0,0 +1,19 @@
+/* { dg-do compile }  */
+/* { dg-options "-O2 -mavx512f" } */
+/* { dg-final { scan-assembler-times "vmovupd.*, %zmm0" 1 } } */
+/* { dg-final { scan-assembler "and\[lq\]?\[\\t \]*\\$-64,\[\\t \]*%\[re\]?sp" } } */
+/* { dg-final { scan-assembler-not "vmovapd.*, %zmm0" } } */
+
+typedef double v4df __attribute__((vector_size(32)));
+typedef double v8df __attribute__((vector_size(64)));
+typedef struct {
+  v4df a[2];
+} c __attribute__((aligned(64)));
+v8df d;
+c v;
+
+void
+foo (float a1, float a2, float a3, float a4, float a5, float a6, c f)
+{
+  d = *(v8df *) &f;
+}