This is a backport of the ARM ABI fix, except that it doesn't change code,
only adds the ABI warning.
So there were four changes, three of them are changing "else if (res < 0)"
to "if (res != 0)" and the fourth was the "res != 0" change in
arm_function_arg_boundary.
I've verified on a testcase that we now get the warning but there are no
changes in .s files.
Bootstrapped/regtested on armv7hl-linux-gnueabi, ok for 6?
2017-04-26 Marek Polacek <pola...@redhat.com>
Ramana Radhakrishnan <ramana.radhakrish...@arm.com>
Jakub Jelinek <ja...@redhat.com>
PR target/77728
* config/arm/arm.c: Include gimple.h.
(aapcs_layout_arg): Emit -Wpsabi note if arm_needs_doubleword_align
returns negative, increment ncrn if it returned non-zero.
(arm_needs_doubleword_align): Return int instead of bool,
ignore DECL_ALIGN of non-FIELD_DECL TYPE_FIELDS chain
members, but if there is any such non-FIELD_DECL
> PARM_BOUNDARY aligned decl, return -1 instead of false.
(arm_function_arg): Emit -Wpsabi note if arm_needs_doubleword_align
returns negative, increment nregs if it returned non-zero.
(arm_setup_incoming_varargs): Likewise.
(arm_function_arg_boundary): Emit -Wpsabi note if
arm_needs_doubleword_align returns negative, return
DOUBLEWORD_ALIGNMENT if it returned non-zero.
* g++.dg/abi/pr77728-1.C: New test.
diff --git gcc/config/arm/arm.c gcc/config/arm/arm.c
index 6373103..b3da8c8 100644
--- gcc/config/arm/arm.c
+++ gcc/config/arm/arm.c
@@ -61,6 +61,7 @@
#include "builtins.h"
#include "tm-constrs.h"
#include "rtl-iter.h"
+#include "gimple.h"
/* This file should be included last. */
#include "target-def.h"
@@ -78,7 +79,7 @@ struct four_ints
/* Forward function declarations. */
static bool arm_const_not_ok_for_debug_p (rtx);
-static bool arm_needs_doubleword_align (machine_mode, const_tree);
+static int arm_needs_doubleword_align (machine_mode, const_tree);
static int arm_compute_static_chain_stack_bytes (void);
static arm_stack_offsets *arm_get_frame_offsets (void);
static void arm_add_gc_roots (void);
@@ -6137,8 +6138,20 @@ aapcs_layout_arg (CUMULATIVE_ARGS *pcum, machine_mode
mode,
/* C3 - For double-word aligned arguments, round the NCRN up to the
next even number. */
ncrn = pcum->aapcs_ncrn;
- if ((ncrn & 1) && arm_needs_doubleword_align (mode, type))
- ncrn++;
+ if (ncrn & 1)
+ {
+ int res = arm_needs_doubleword_align (mode, type);
+ /* Only warn during RTL expansion of call stmts, otherwise we would
+ warn e.g. during gimplification even on functions that will be
+ always inlined, and we'd warn multiple times. Don't warn when
+ called in expand_function_start either, as we warn instead in
+ arm_function_arg_boundary in that case. */
+ if (res < 0 && warn_psabi && currently_expanding_gimple_stmt)
+ inform (input_location, "parameter passing for argument of type "
+ "%qT will change in GCC 7.1", type);
+ if (res != 0)
+ ncrn++;
+ }
nregs = ARM_NUM_REGS2(mode, type);
@@ -6243,12 +6256,16 @@ arm_init_cumulative_args (CUMULATIVE_ARGS *pcum, tree
fntype,
}
}
-/* Return true if mode/type need doubleword alignment. */
-static bool
+/* Return 1 if double word alignment is required for argument passing.
+ Return -1 if double word alignment used to be required for argument
+ passing before PR77728 ABI fix, but is not required anymore.
+ Return 0 if double word alignment is not required and wasn't requried
+ before either. */
+static int
arm_needs_doubleword_align (machine_mode mode, const_tree type)
{
if (!type)
- return PARM_BOUNDARY < GET_MODE_ALIGNMENT (mode);
+ return GET_MODE_ALIGNMENT (mode) > PARM_BOUNDARY;
/* Scalar and vector types: Use natural alignment, i.e. of base type. */
if (!AGGREGATE_TYPE_P (type))
@@ -6258,12 +6275,21 @@ arm_needs_doubleword_align (machine_mode mode,
const_tree type)
if (TREE_CODE (type) == ARRAY_TYPE)
return TYPE_ALIGN (TREE_TYPE (type)) > PARM_BOUNDARY;
+ int ret = 0;
/* Record/aggregate types: Use greatest member alignment of any member. */
for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
if (DECL_ALIGN (field) > PARM_BOUNDARY)
- return true;
+ {
+ if (TREE_CODE (field) == FIELD_DECL)
+ return 1;
+ else
+ /* Before PR77728 fix, we were incorrectly considering also
+ other aggregate fields, like VAR_DECLs, TYPE_DECLs etc.
+ Make sure we can warn about that with -Wpsabi. */
+ ret = -1;
+ }
- return false;
+ return ret;
}
@@ -6320,10 +6346,15 @@ arm_function_arg (cumulative_args_t pcum_v,
machine_mode mode,
}
/* Put doubleword aligned quantities in even register pairs. */
- if (pcum->nregs & 1
- && ARM_DOUBLEWORD_ALIGN
- && arm_needs_doubleword_align (mode, type))
- pcum->nregs++;
+ if ((pcum->nregs & 1) && ARM_DOUBLEWORD_ALIGN)
+ {
+ int res = arm_needs_doubleword_align (mode, type);
+ if (res < 0 && warn_psabi)
+ inform (input_location, "parameter passing for argument of type "
+ "%qT will change in GCC 7.1", type);
+ if (res != 0)
+ pcum->nregs++;
+ }
/* Only allow splitting an arg between regs and memory if all preceding
args were allocated to regs. For args passed by reference we only count
@@ -6342,9 +6373,15 @@ arm_function_arg (cumulative_args_t pcum_v, machine_mode
mode,
static unsigned int
arm_function_arg_boundary (machine_mode mode, const_tree type)
{
- return (ARM_DOUBLEWORD_ALIGN && arm_needs_doubleword_align (mode, type)
- ? DOUBLEWORD_ALIGNMENT
- : PARM_BOUNDARY);
+ if (!ARM_DOUBLEWORD_ALIGN)
+ return PARM_BOUNDARY;
+
+ int res = arm_needs_doubleword_align (mode, type);
+ if (res < 0 && warn_psabi)
+ inform (input_location, "parameter passing for argument of type %qT "
+ "will change in GCC 7.1", type);
+
+ return res != 0 ? DOUBLEWORD_ALIGNMENT : PARM_BOUNDARY;
}
static int
@@ -26402,8 +26439,15 @@ arm_setup_incoming_varargs (cumulative_args_t pcum_v,
if (pcum->pcs_variant <= ARM_PCS_AAPCS_LOCAL)
{
nregs = pcum->aapcs_ncrn;
- if ((nregs & 1) && arm_needs_doubleword_align (mode, type))
- nregs++;
+ if (nregs & 1)
+ {
+ int res = arm_needs_doubleword_align (mode, type);
+ if (res < 0 && warn_psabi)
+ inform (input_location, "parameter passing for argument of "
+ "type %qT will change in GCC 7.1", type);
+ if (res != 0)
+ nregs++;
+ }
}
else
nregs = pcum->nregs;
diff --git gcc/testsuite/g++.dg/abi/pr77728-1.C
gcc/testsuite/g++.dg/abi/pr77728-1.C
index e69de29..05f08c9 100644
--- gcc/testsuite/g++.dg/abi/pr77728-1.C
+++ gcc/testsuite/g++.dg/abi/pr77728-1.C
@@ -0,0 +1,171 @@
+// { dg-do compile { target arm_eabi } }
+// { dg-options "-Wpsabi" }
+
+#include <stdarg.h>
+
+template <int N>
+struct A { double p; };
+
+A<0> v;
+
+template <int N>
+struct B
+{
+ typedef A<N> T;
+ int i, j;
+};
+
+struct C : public B<0> {};
+struct D {};
+struct E : public D, C {};
+struct F : public B<1> {};
+struct G : public F { static double y; };
+struct H : public G {};
+struct I : public D { long long z; };
+struct J : public D { static double z; int i, j; };
+
+template <int N>
+struct K : public D { typedef A<N> T; int i, j; };
+
+struct L { static double h; int i, j; };
+
+int
+fn1 (int a, B<0> b) // { dg-message "note: parameter passing for argument
of type \[^\n\r]* will change in GCC 7\.1" }
+{
+ return a + b.i;
+}
+
+int
+fn2 (int a, B<1> b)
+{
+ return a + b.i;
+}
+
+int
+fn3 (int a, L b) // { dg-message "note: parameter passing for argument
of type \[^\n\r]* will change in GCC 7\.1" }
+{
+ return a + b.i;
+}
+
+int
+fn4 (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, B<0> n, ...)
+// { dg-message "note: parameter passing for argument of type \[^\n\r]* will
change in GCC 7\.1" "" { target *-*-* } .-1 }
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn5 (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, B<1> n, ...)
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn6 (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, C n, ...)
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn7 (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, E n, ...)
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn8 (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, H n, ...)
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn9 (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, I n, ...)
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn10 (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, J n, ...)
+// { dg-message "note: parameter passing for argument of type \[^\n\r]* will
change in GCC 7\.1" "" { target *-*-* } .-1 }
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn11 (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, K<0> n, ...)
+// { dg-message "note: parameter passing for argument of type \[^\n\r]* will
change in GCC 7\.1" "" { target *-*-* } .-1 }
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+int
+fn12 (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, K<2> n, ...)
+{
+ va_list ap;
+ va_start (ap, n);
+ int x = va_arg (ap, int);
+ va_end (ap);
+ return x;
+}
+
+void
+test ()
+{
+ static B<0> b0;
+ static B<1> b1;
+ static L l;
+ static C c;
+ static E e;
+ static H h;
+ static I i;
+ static J j;
+ static K<0> k0;
+ static K<2> k2;
+ fn1 (1, b0); // { dg-message "note: parameter passing for argument of type
\[^\n\r]* will change in GCC 7\.1" }
+ fn2 (1, b1);
+ fn3 (1, l); // { dg-message "note: parameter passing for argument of type
\[^\n\r]* will change in GCC 7\.1" }
+ fn4 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, b0, 1, 2, 3, 4);
+ // { dg-message "note: parameter passing for argument of type \[^\n\r]* will
change in GCC 7\.1" "" { target *-*-* } .-1 }
+ fn5 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, b1, 1, 2, 3, 4);
+ fn6 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, c, 1, 2, 3, 4);
+ fn7 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, e, 1, 2, 3, 4);
+ fn8 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, h, 1, 2, 3, 4);
+ fn9 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, i, 1, 2, 3, 4);
+ fn10 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, j, 1, 2, 3, 4);
+ // { dg-message "note: parameter passing for argument of type \[^\n\r]* will
change in GCC 7\.1" "" { target *-*-* } .-1 }
+ fn11 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, k0, 1, 2, 3, 4);
+ // { dg-message "note: parameter passing for argument of type \[^\n\r]* will
change in GCC 7\.1" "" { target *-*-* } .-1 }
+ fn12 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, k2, 1, 2, 3, 4);
+}
Marek
