On December 10, 2019 12:44:01 PM GMT+01:00, Richard Sandiford
<richard.sandif...@arm.com> wrote:
>The dwarf2 handling of vector constants currently divides the vector
>into a length (number of elements) and byte element size. This doesn't
>work well for MODE_VECTOR_BOOL, where several elements are packed into
>the same byte.
>
>We should probably add a way of encoding this in future, but for now
>the safest thing is to punt, like we already do for variable-length
>vectors.
>
>Tested on aarch64-linux-gnu and x86_64-linux-gnu. OK to install?
Ok.
Richard.
>Richard
>
>
>2019-12-10 Richard Sandiford <richard.sandif...@arm.com>
>
>gcc/
> * dwarf2out.c (loc_descriptor): Punt for MODE_VECTOR_BOOL.
> (add_const_value_attribute): Likewise.
>
>gcc/testsuite/
> * gcc.target/aarch64/sve/acle/general/debug_4.c: New test.
>
>Index: gcc/dwarf2out.c
>===================================================================
>--- gcc/dwarf2out.c 2019-11-29 13:04:13.978672241 +0000
>+++ gcc/dwarf2out.c 2019-12-10 11:43:15.560875505 +0000
>@@ -16763,7 +16763,12 @@ loc_descriptor (rtx rtl, machine_mode mo
> if (mode == VOIDmode)
> mode = GET_MODE (rtl);
>
>- if (mode != VOIDmode && (dwarf_version >= 4 || !dwarf_strict))
>+ if (mode != VOIDmode
>+ /* The combination of a length and byte elt_size doesn't extend
>+ naturally to boolean vectors, where several elements are packed
>+ into the same byte. */
>+ && GET_MODE_CLASS (mode) != MODE_VECTOR_BOOL
>+ && (dwarf_version >= 4 || !dwarf_strict))
> {
> unsigned int length;
> if (!CONST_VECTOR_NUNITS (rtl).is_constant (&length))
>@@ -19622,6 +19627,12 @@ add_const_value_attribute (dw_die_ref di
> return false;
>
> machine_mode mode = GET_MODE (rtl);
>+ /* The combination of a length and byte elt_size doesn't extend
>+ naturally to boolean vectors, where several elements are packed
>+ into the same byte. */
>+ if (GET_MODE_CLASS (mode) == MODE_VECTOR_BOOL)
>+ return false;
>+
> unsigned int elt_size = GET_MODE_UNIT_SIZE (mode);
> unsigned char *array
> = ggc_vec_alloc<unsigned char> (length * elt_size);
>Index: gcc/testsuite/gcc.target/aarch64/sve/acle/general/debug_4.c
>===================================================================
>--- /dev/null 2019-09-17 11:41:18.176664108 +0100
>+++
>gcc/testsuite/gcc.target/aarch64/sve/acle/general/debug_4.c 2019-12-10
>11:43:15.572875421 +0000
>@@ -0,0 +1,16 @@
>+/* { dg-options "-O -g -msve-vector-bits=512" } */
>+
>+#include <arm_sve.h>
>+
>+void __attribute__((noipa))
>+g (volatile int *x, svbool_t pg)
>+{
>+ *x = 1;
>+}
>+
>+void
>+f (volatile int *x)
>+{
>+ svbool_t pg = svorr_z (svpfalse (), svpfalse (), svpfalse ());
>+ g (x, pg);
>+}
