[PATCH] Allow __ibm128 on older PowerPC systems.
On January 8th, 2018, I added code to ibm-ldouble.c to use the built-in
function __builtin_pack_ibm128 if long double is IEEE 128-bit and continue to
use __builtin_pack_longdouble if long double is IBM extended double. This code
was needed because __builtin_pack_ibm128 is not available unless the __ibm128
keyword is availabe. In the current code, __ibm128 is only enabled if we have
support for both IBM and IEEE 128-bit long double.
Segher suggested that instead I should make __ibm128, __builtin_pack_ibm128,
and __builtin_unpack_ibm128 available on older systems that don't support IEEE
128-bit floating point but does support the IBM extended double floating point.
This patch changes the code so that __ibm128 is now exported if either
long double uses the IBM extended double format, or IEEE 128-bit floating
point is available.
I changed the internal built-in types from float128 to ibm128, since the
only built-in functions that use this are __builtin_pack_ibm128 and
__builtin_unpack_ibm128, and the new name matches the function.
In addition, this patch changes the function within libgcc that handles
IBM long double to use the __builtin_pack_ibm128 function.
I have done bootstrap builds with this patch on the following 3 systems:
1) power9 running LE Linux using --with-cpu=power9
2) power8 running BE Linux using --with-cpu=power8, testing both
32/64-bit.
3) power10 prototype running LE Linux using --with-cpu=power10.
There were no regressions to the tests, and the new test added passed. Can I
check these patches into trunk branch for GCC 12?
At the moment, I'm not sure this should be backported to GCC 11. But I can
easily do the back port after a stabilizing period.
gcc/
2021-05-18 Michael Meissner <meiss...@linux.ibm.com>
* config/rs6000/rs6000-builtin.def (BU_IBM128_2): Rename
RS6000_BTM_IBM128 from RS6000_BTM_FLOAT128.
* config/rs6000/rs6000-call.c (rs6000_invalid_builtin): Update
error message for __ibm128 built-in functions.
(rs6000_init_builtins): Create the __ibm128 keyword on older
systems where long double uses the IBM extended double format,
even if they don't support IEEE 128-bit floating point.
* config/rs6000/rs6000.c (rs6000_builtin_mask_calculate): Rename
RS6000_BTM_IBM128 from RS6000_BTM_FLOAT128.
(rs6000_builtin_mask_names): Rename RS6000_BTM_IBM128 from
RS6000_BTM_FLOAT128.
* config/rs6000/rs6000.h (TARGET_IBM128): New macro.
(RS6000_BTM_IBM128): Rename from RS6000_BTM_FLOAT128.
(RS6000_BTM_COMMON): Rename RS6000_BTM_IBM128 from
RS6000_BTM_FLOAT128.
libgcc/
2021-05-18 Michael Meissner <meiss...@linux.ibm.com>
* config/rs6000/ibm-ldouble.c (pack_ldouble): Use
__builtin_pack_ibm128 instead of __builtin_pack_longdouble.
---
gcc/config/rs6000/rs6000-builtin.def | 5 ++---
gcc/config/rs6000/rs6000-call.c | 14 ++++++++++----
gcc/config/rs6000/rs6000.c | 4 ++--
gcc/config/rs6000/rs6000.h | 12 +++++++++---
libgcc/config/rs6000/ibm-ldouble.c | 4 ++--
5 files changed, 25 insertions(+), 14 deletions(-)
diff --git a/gcc/config/rs6000/rs6000-builtin.def
b/gcc/config/rs6000/rs6000-builtin.def
index 609bebdfd74..6d82ed224fb 100644
--- a/gcc/config/rs6000/rs6000-builtin.def
+++ b/gcc/config/rs6000/rs6000-builtin.def
@@ -796,13 +796,12 @@
| RS6000_BTC_BINARY), \
CODE_FOR_ ## ICODE) /* ICODE */
-/* 128-bit __ibm128 floating point builtins (use -mfloat128 to indicate that
- __ibm128 is available). */
+/* 128-bit __ibm128 floating point builtins. */
#define BU_IBM128_2(ENUM, NAME, ATTR, ICODE) \
RS6000_BUILTIN_2 (MISC_BUILTIN_ ## ENUM, /* ENUM */ \
"__builtin_" NAME, /* NAME */ \
(RS6000_BTM_HARD_FLOAT /* MASK */ \
- | RS6000_BTM_FLOAT128), \
+ | RS6000_BTM_IBM128), \
(RS6000_BTC_ ## ATTR /* ATTR */ \
| RS6000_BTC_BINARY), \
CODE_FOR_ ## ICODE) /* ICODE */
diff --git a/gcc/config/rs6000/rs6000-call.c b/gcc/config/rs6000/rs6000-call.c
index c4332a61862..7bdc4eeca5f 100644
--- a/gcc/config/rs6000/rs6000-call.c
+++ b/gcc/config/rs6000/rs6000-call.c
@@ -11540,8 +11540,8 @@ rs6000_invalid_builtin (enum rs6000_builtins fncode)
error ("%qs requires the %qs option", name, "-mhard-float");
else if ((fnmask & RS6000_BTM_FLOAT128_HW) != 0)
error ("%qs requires ISA 3.0 IEEE 128-bit floating point", name);
- else if ((fnmask & RS6000_BTM_FLOAT128) != 0)
- error ("%qs requires the %qs option", name, "%<-mfloat128%>");
+ else if ((fnmask & RS6000_BTM_IBM128) != 0)
+ error ("%qs requires the IBM 128-bit floating point", name);
else if ((fnmask & (RS6000_BTM_POPCNTD | RS6000_BTM_POWERPC64))
== (RS6000_BTM_POPCNTD | RS6000_BTM_POWERPC64))
error ("%qs requires the %qs (or newer), and %qs or %qs options",
@@ -13236,7 +13236,7 @@ rs6000_init_builtins (void)
For IEEE 128-bit floating point, always create the type __ieee128. If the
user used -mfloat128, rs6000-c.c will create a define from __float128 to
__ieee128. */
- if (TARGET_FLOAT128_TYPE)
+ if (TARGET_IBM128)
{
if (!TARGET_IEEEQUAD && TARGET_LONG_DOUBLE_128)
ibm128_float_type_node = long_double_type_node;
@@ -13250,7 +13250,13 @@ rs6000_init_builtins (void)
lang_hooks.types.register_builtin_type (ibm128_float_type_node,
"__ibm128");
+ }
+
+ else
+ ibm128_float_type_node = long_double_type_node;
+ if (TARGET_FLOAT128_TYPE)
+ {
if (TARGET_IEEEQUAD && TARGET_LONG_DOUBLE_128)
ieee128_float_type_node = long_double_type_node;
else
@@ -13261,7 +13267,7 @@ rs6000_init_builtins (void)
}
else
- ieee128_float_type_node = ibm128_float_type_node = long_double_type_node;
+ ieee128_float_type_node = long_double_type_node;
/* Vector pair and vector quad support. */
if (TARGET_EXTRA_BUILTINS)
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 44ae3adbe7a..86f53297cb9 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -3427,7 +3427,7 @@ rs6000_builtin_mask_calculate (void)
| ((TARGET_LONG_DOUBLE_128
&& TARGET_HARD_FLOAT
&& !TARGET_IEEEQUAD) ? RS6000_BTM_LDBL128 : 0)
- | ((TARGET_FLOAT128_TYPE) ? RS6000_BTM_FLOAT128 : 0)
+ | ((TARGET_IBM128) ? RS6000_BTM_IBM128 : 0)
| ((TARGET_FLOAT128_HW) ? RS6000_BTM_FLOAT128_HW : 0)
| ((TARGET_MMA) ? RS6000_BTM_MMA : 0)
| ((TARGET_POWER10) ? RS6000_BTM_P10 : 0));
@@ -24164,7 +24164,7 @@ static struct rs6000_opt_mask const
rs6000_builtin_mask_names[] =
{ "hard-float", RS6000_BTM_HARD_FLOAT, false, false },
{ "long-double-128", RS6000_BTM_LDBL128, false, false },
{ "powerpc64", RS6000_BTM_POWERPC64, false, false },
- { "float128", RS6000_BTM_FLOAT128, false, false },
+ { "ibm128", RS6000_BTM_IBM128, false, false },
{ "float128-hw", RS6000_BTM_FLOAT128_HW,false, false },
{ "mma", RS6000_BTM_MMA, false, false },
{ "power10", RS6000_BTM_P10, false, false },
diff --git a/gcc/config/rs6000/rs6000.h b/gcc/config/rs6000/rs6000.h
index 164d359b724..b0e1953aeae 100644
--- a/gcc/config/rs6000/rs6000.h
+++ b/gcc/config/rs6000/rs6000.h
@@ -504,6 +504,12 @@ extern int rs6000_vector_align[];
#define TARGET_MINMAX (TARGET_HARD_FLOAT && TARGET_PPC_GFXOPT \
&& (TARGET_P9_MINMAX || !flag_trapping_math))
+/* Whether the '__ibm128' keywork is enabled. We enable __ibm128 either if the
+ IEEE 128-bit floating point support is enabled or if the long double support
+ uses the 128-bit IBM extended double format. */
+#define TARGET_IBM128 (TARGET_FLOAT128_TYPE \
+ || (!TARGET_IEEEQUAD && TARGET_LONG_DOUBLE_128))
+
/* In switching from using target_flags to using rs6000_isa_flags, the options
machinery creates OPTION_MASK_<xxx> instead of MASK_<xxx>. For now map
OPTION_MASK_<xxx> back into MASK_<xxx>. */
@@ -2305,7 +2311,7 @@ extern int frame_pointer_needed;
#define RS6000_BTC_SAT RS6000_BTC_MISC /* saturate sets VSCR. */
/* Builtin targets. For now, we reuse the masks for those options that are in
- target flags, and pick a random bit for ldbl128, which isn't in
+ target flags, and pick a random bit for ldbl128 and ibm128, which aren't in
target_flags. */
#define RS6000_BTM_ALWAYS 0 /* Always enabled. */
#define RS6000_BTM_ALTIVEC MASK_ALTIVEC /* VMX/altivec vectors. */
@@ -2327,7 +2333,7 @@ extern int frame_pointer_needed;
#define RS6000_BTM_LDBL128 MASK_MULTIPLE /* 128-bit long double. */
#define RS6000_BTM_64BIT MASK_64BIT /* 64-bit addressing. */
#define RS6000_BTM_POWERPC64 MASK_POWERPC64 /* 64-bit registers. */
-#define RS6000_BTM_FLOAT128 MASK_FLOAT128_KEYWORD /* IEEE 128-bit float. */
+#define RS6000_BTM_IBM128 MASK_FLOAT128_KEYWORD /* __ibm128 keyword. */
#define RS6000_BTM_FLOAT128_HW MASK_FLOAT128_HW /* IEEE 128-bit float h/w. */
#define RS6000_BTM_MMA MASK_MMA /* ISA 3.1 MMA. */
#define RS6000_BTM_P10 MASK_POWER10
@@ -2351,7 +2357,7 @@ extern int frame_pointer_needed;
| RS6000_BTM_HARD_FLOAT \
| RS6000_BTM_LDBL128 \
| RS6000_BTM_POWERPC64 \
- | RS6000_BTM_FLOAT128 \
+ | RS6000_BTM_IBM128 \
| RS6000_BTM_FLOAT128_HW \
| RS6000_BTM_MMA \
| RS6000_BTM_P10)
diff --git a/libgcc/config/rs6000/ibm-ldouble.c
b/libgcc/config/rs6000/ibm-ldouble.c
index 4c13453f975..92b4b4c583d 100644
--- a/libgcc/config/rs6000/ibm-ldouble.c
+++ b/libgcc/config/rs6000/ibm-ldouble.c
@@ -102,9 +102,9 @@ __asm__ (".symver __gcc_qadd,_xlqadd@GCC_3.4\n\t"
static inline IBM128_TYPE
pack_ldouble (double dh, double dl)
{
-#if defined (__LONG_DOUBLE_128__) && defined (__LONG_DOUBLE_IBM128__) \
+#if defined (__LONG_DOUBLE_128__) \
&& !(defined (_SOFT_FLOAT) || defined (__NO_FPRS__))
- return __builtin_pack_longdouble (dh, dl);
+ return __builtin_pack_ibm128 (dh, dl);
#else
union
{
--
2.31.1
--
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
