Ping.
On Thu, Apr 27, 2017 at 12:44:42PM +0200, Marek Polacek wrote:
> 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
Marek
