* Claudiu Zissulescu <claudiu.zissule...@synopsys.com> [2017-11-27 12:09:50
+0100]:
> From: Claudiu Zissulescu <claz...@gmail.com>
>
> Sometimes the memory equivalent is not valid due to a large offset.
> For example replacing the ap register with its fp/sp-equivalent during
> LRA step. To solve this we introduced TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV.
>
> gcc/
> 2017-08-08 Claudiu Zissulescu <claz...@synopsys.com>
>
> * config/arc/arc.c (arc_cannot_substitute_mem_equiv_p): New function.
> (TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P): Define.
>
> gcc/testsuite
> 2017-08-08 Claudiu Zissulescu <claz...@synopsys.com>
>
> * gcc.target/arc/lra-1.c: New test.
Looks good.
Thanks,
Andrew
> ---
> gcc/config/arc/arc.c | 12 ++++++++++++
> gcc/testsuite/gcc.target/arc/lra-1.c | 17 +++++++++++++++++
> 2 files changed, 29 insertions(+)
> create mode 100644 gcc/testsuite/gcc.target/arc/lra-1.c
>
> diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c
> index dd922a6..25f123c 100644
> --- a/gcc/config/arc/arc.c
> +++ b/gcc/config/arc/arc.c
> @@ -11352,12 +11352,24 @@ arc_use_anchors_for_symbol_p (const_rtx symbol)
> return default_use_anchors_for_symbol_p (symbol);
> }
>
> +/* Return true if SUBST can't safely replace its equivalent during RA. */
> +static bool
> +arc_cannot_substitute_mem_equiv_p (rtx)
> +{
> + /* If SUBST is mem[base+index], the address may not fit iSA,
> + thus return true. */
> + return true;
> +}
> +
> #undef TARGET_USE_ANCHORS_FOR_SYMBOL_P
> #define TARGET_USE_ANCHORS_FOR_SYMBOL_P arc_use_anchors_for_symbol_p
>
> #undef TARGET_CONSTANT_ALIGNMENT
> #define TARGET_CONSTANT_ALIGNMENT constant_alignment_word_strings
>
> +#undef TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P
> +#define TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P
> arc_cannot_substitute_mem_equiv_p
> +
> struct gcc_target targetm = TARGET_INITIALIZER;
>
> #include "gt-arc.h"
> diff --git a/gcc/testsuite/gcc.target/arc/lra-1.c
> b/gcc/testsuite/gcc.target/arc/lra-1.c
> new file mode 100644
> index 0000000..27336d1
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/arc/lra-1.c
> @@ -0,0 +1,17 @@
> +/* { dg-do compile } */
> +/* { dg-options "-Os -w -mlra" } */
> +
> +/* ap is replaced with an address like base+offset by lra,
> + where offset is larger than s9, resulting into an ICE. */
> +
> +typedef struct { char a[500] } b;
> +c;
> +struct d {
> + short e;
> + b f
> +} g(int h, int i, int j, int k, char l, int m, int n, char *p) {
> +again:;
> + struct d o;
> + *p = c = ({ q(o); });
> + goto again;
> +}
> --
> 1.9.1
>
