This patch assumes patches #1 through #10 have been applied. Once all of those
patches have been applied, this patch will change the default for Linux 64-bit
systems to enable -mpcrel and -mprefixed-addr being default when -mcpu=future
is used. The other OS/bit-size targets (currently) do not enable these
options.
Along with the other patches, I have done bootstraps on a little endian power8
system, and there were no regressions in the test suite. Can I check this into
the trunk?
2019-10-08 Michael Meissner <meiss...@linux.ibm.com>
* config/rs6000/linux64.h (TARGET_PREFIXED_ADDR_DEFAULT): Enable
prefixed addressing by default.
(TARGET_PCREL_DEFAULT): Enable pc-relative addressing by default.
* config/rs6000/rs6000-cpus.def (ISA_FUTURE_MASKS_SERVER): Only
enable -mprefixed-addr and -mpcrel if the OS tm.h says to enable
it.
(ADDRESSING_FUTURE_MASKS): New mask macro.
(OTHER_FUTURE_MASKS): Use ADDRESSING_FUTURE_MASKS.
* config/rs6000/rs6000.c (TARGET_PREFIXED_ADDR_DEFAULT): Do not
enable -mprefixed-addr unless the OS tm.h says to.
(TARGET_PCREL_DEFAULT): Do not enable -mpcrel unless the OS tm.h
says to.
(rs6000_option_override_internal): Do not enable -mprefixed-addr
or -mpcrel unless the OS tm.h says to enable it. Add more checks
for -mcpu=future.
Index: gcc/config/rs6000/linux64.h
===================================================================
--- gcc/config/rs6000/linux64.h (revision 276713)
+++ gcc/config/rs6000/linux64.h (working copy)
@@ -640,3 +640,11 @@ extern int dot_symbols;
enabling the __float128 keyword. */
#undef TARGET_FLOAT128_ENABLE_TYPE
#define TARGET_FLOAT128_ENABLE_TYPE 1
+
+/* Enable support for pc-relative and numeric prefixed addressing on the
+ 'future' system. */
+#undef TARGET_PREFIXED_ADDR_DEFAULT
+#define TARGET_PREFIXED_ADDR_DEFAULT 1
+
+#undef TARGET_PCREL_DEFAULT
+#define TARGET_PCREL_DEFAULT 1
Index: gcc/config/rs6000/rs6000-cpus.def
===================================================================
--- gcc/config/rs6000/rs6000-cpus.def (revision 276713)
+++ gcc/config/rs6000/rs6000-cpus.def (working copy)
@@ -75,15 +75,21 @@
| OPTION_MASK_P8_VECTOR \
| OPTION_MASK_P9_VECTOR)
-/* Support for a future processor's features. Do not enable -mpcrel until it
- is fully functional. */
+/* Support for a future processor's features. The prefixed and pc-relative
+ addressing bits are not added here. Instead, rs6000.c adds them if the OS
+ tm.h says that it supports the addressing modes. */
#define ISA_FUTURE_MASKS_SERVER (ISA_3_0_MASKS_SERVER
\
- | OPTION_MASK_FUTURE \
+ | OPTION_MASK_FUTURE)
+
+/* Addressing related flags on a future processor. These flags are broken out
+ because not all targets will support either pc-relative addressing, or even
+ prefixed addressing, and we want to clear all of the addressing bits
+ on targets that cannot support prefixed/pcrel addressing. */
+#define ADDRESSING_FUTURE_MASKS (OPTION_MASK_PCREL
\
| OPTION_MASK_PREFIXED_ADDR)
/* Flags that need to be turned off if -mno-future. */
-#define OTHER_FUTURE_MASKS (OPTION_MASK_PCREL \
- | OPTION_MASK_PREFIXED_ADDR)
+#define OTHER_FUTURE_MASKS ADDRESSING_FUTURE_MASKS
/* Flags that need to be turned off if -mno-power9-vector. */
#define OTHER_P9_VECTOR_MASKS (OPTION_MASK_FLOAT128_HW \
Index: gcc/config/rs6000/rs6000.c
===================================================================
--- gcc/config/rs6000/rs6000.c (revision 276724)
+++ gcc/config/rs6000/rs6000.c (working copy)
@@ -98,6 +98,16 @@
#endif
#endif
+/* Set up the defaults for whether prefixed addressing is used, and if it is
+ used, whether we want to turn on pc-relative support by default. */
+#ifndef TARGET_PREFIXED_ADDR_DEFAULT
+#define TARGET_PREFIXED_ADDR_DEFAULT 0
+#endif
+
+#ifndef TARGET_PCREL_DEFAULT
+#define TARGET_PCREL_DEFAULT 0
+#endif
+
/* Support targetm.vectorize.builtin_mask_for_load. */
GTY(()) tree altivec_builtin_mask_for_load;
@@ -2532,6 +2542,14 @@ rs6000_debug_reg_global (void)
if (TARGET_DIRECT_MOVE_128)
fprintf (stderr, DEBUG_FMT_D, "VSX easy 64-bit mfvsrld element",
(int)VECTOR_ELEMENT_MFVSRLD_64BIT);
+
+ if (TARGET_FUTURE)
+ {
+ fprintf (stderr, DEBUG_FMT_D, "TARGET_PREFIXED_ADDR_DEFAULT",
+ TARGET_PREFIXED_ADDR_DEFAULT);
+ fprintf (stderr, DEBUG_FMT_D, "TARGET_PCREL_DEFAULT",
+ TARGET_PCREL_DEFAULT);
+ }
}
@@ -4012,26 +4030,6 @@ rs6000_option_override_internal (bool gl
rs6000_isa_flags &= ~OPTION_MASK_FLOAT128_HW;
}
- /* -mprefixed-addr (and hence -mpcrel) requires -mcpu=future. */
- if (TARGET_PREFIXED_ADDR && !TARGET_FUTURE)
- {
- if ((rs6000_isa_flags_explicit & OPTION_MASK_PCREL) != 0)
- error ("%qs requires %qs", "-mpcrel", "-mcpu=future");
- else if ((rs6000_isa_flags_explicit & OPTION_MASK_PREFIXED_ADDR) != 0)
- error ("%qs requires %qs", "-mprefixed-addr", "-mcpu=future");
-
- rs6000_isa_flags &= ~(OPTION_MASK_PCREL | OPTION_MASK_PREFIXED_ADDR);
- }
-
- /* -mpcrel requires prefixed load/store addressing. */
- if (TARGET_PCREL && !TARGET_PREFIXED_ADDR)
- {
- if ((rs6000_isa_flags_explicit & OPTION_MASK_PCREL) != 0)
- error ("%qs requires %qs", "-mpcrel", "-mprefixed-addr");
-
- rs6000_isa_flags &= ~OPTION_MASK_PCREL;
- }
-
/* Print the options after updating the defaults. */
if (TARGET_DEBUG_REG || TARGET_DEBUG_TARGET)
rs6000_print_isa_options (stderr, 0, "after defaults", rs6000_isa_flags);
@@ -4163,12 +4161,89 @@ rs6000_option_override_internal (bool gl
SUB3TARGET_OVERRIDE_OPTIONS;
#endif
- /* -mpcrel requires -mcmodel=medium, but we can't check TARGET_CMODEL until
- after the subtarget override options are done. */
- if (TARGET_PCREL && TARGET_CMODEL != CMODEL_MEDIUM)
+ /* Enable prefixed addressing and pc-relative addressing on 64-bit ELF v2
+ systems if the OS tm.h file says that it is supported and the user did not
+ explicitly use -mprefixed-addr or -mpcrel. At the present time, only
+ 64-bit Linux enables this.
+
+ Pc-relative support also requires the medium code model.
+
+ However, we can't check for ELFv2 or -mcmodel=medium until after the
+ subtarget macros are run.
+
+ If prefixed addressing is disabled by default, and the user does -mpcrel,
+ don't force them to also specify -mprefixed-addr. */
+ if (TARGET_FUTURE)
+ {
+ bool explicit_prefixed = ((rs6000_isa_flags_explicit
+ & OPTION_MASK_PREFIXED_ADDR) != 0);
+ bool explicit_pcrel = ((rs6000_isa_flags_explicit
+ & OPTION_MASK_PCREL) != 0);
+
+ /* Prefixed addressing requires 64-bit registers. */
+ if (!TARGET_POWERPC64)
+ {
+ if (TARGET_PCREL && explicit_pcrel)
+ error ("%qs requires %qs", "-mpcrel", "-m64");
+
+ else if (TARGET_PREFIXED_ADDR && explicit_prefixed)
+ error ("%qs requires %qs", "-mprefixed-addr", "-m64");
+
+ rs6000_isa_flags &= ~ADDRESSING_FUTURE_MASKS;
+ }
+
+ /* Only ELFv2 currently supports prefixed/pcrel addressing. */
+ else if (rs6000_current_abi != ABI_ELFv2)
+ {
+ if (TARGET_PCREL && explicit_pcrel)
+ error ("%qs requires %qs", "-mpcrel", "-mabi=elfv2");
+
+ else if (TARGET_PREFIXED_ADDR && explicit_prefixed)
+ error ("%qs requires %qs", "-mprefixed-addr", "-mabi=elfv2");
+
+ rs6000_isa_flags &= ~ADDRESSING_FUTURE_MASKS;
+ }
+
+ /* Pc-relative requires the medium code model. */
+ else if (TARGET_PCREL && TARGET_CMODEL != CMODEL_MEDIUM)
+ {
+ if ((rs6000_isa_flags_explicit & OPTION_MASK_PCREL) != 0)
+ error ("%qs requires %qs", "-mpcrel", "-mcmodel=medium");
+
+ rs6000_isa_flags &= ~OPTION_MASK_PCREL;
+ }
+
+ /* Enable defaults if desired. */
+ else
+ {
+ if (!explicit_prefixed
+ && (TARGET_PREFIXED_ADDR_DEFAULT
+ || TARGET_PCREL
+ || TARGET_PCREL_DEFAULT))
+ rs6000_isa_flags |= OPTION_MASK_PREFIXED_ADDR;
+
+ if (!explicit_pcrel && TARGET_PCREL_DEFAULT
+ && TARGET_CMODEL == CMODEL_MEDIUM)
+ rs6000_isa_flags |= OPTION_MASK_PCREL;
+ }
+ }
+
+ /* -mprefixed-addr (and hence -mpcrel) requires -mcpu=future. */
+ if (TARGET_PREFIXED_ADDR && !TARGET_FUTURE)
{
if ((rs6000_isa_flags_explicit & OPTION_MASK_PCREL) != 0)
- error ("%qs requires %qs", "-mpcrel", "-mcmodel=medium");
+ error ("%qs requires %qs", "-mpcrel", "-mcpu=future");
+ else if ((rs6000_isa_flags_explicit & OPTION_MASK_PREFIXED_ADDR) != 0)
+ error ("%qs requires %qs", "-mprefixed-addr", "-mcpu=future");
+
+ rs6000_isa_flags &= ~(OPTION_MASK_PCREL | OPTION_MASK_PREFIXED_ADDR);
+ }
+
+ /* -mpcrel requires prefixed load/store addressing. */
+ if (TARGET_PCREL && !TARGET_PREFIXED_ADDR)
+ {
+ if ((rs6000_isa_flags_explicit & OPTION_MASK_PCREL) != 0)
+ error ("%qs requires %qs", "-mpcrel", "-mprefixed-addr");
rs6000_isa_flags &= ~OPTION_MASK_PCREL;
}
--
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meiss...@linux.ibm.com, phone: +1 (978) 899-4797
