On Thu, Jul 13, 2017 at 03:57:08PM -0500, Segher Boessenkool wrote:
> On Wed, Jul 12, 2017 at 07:19:27PM -0400, Michael Meissner wrote:
> > Hmmm, I didn't realize that gcc 6.x also supported __builtin_cpu_*. I
> > imagine
> > we will need backports there as well.
>
> Okay for 6 too if needed there (do testcases warn us for that?)
I have patches for both 6 and 7. I had to back port the change in
testsuite/lib/target-supports.exp for ppc_cpu_supports_hw_available in order to
add the dg-requires for the 1 test that is in the testsuite.
The part of the change that changed the target_clones warning to error is not
appropriate for either branch, and that patch has been dropped. The GCC 6
patch for defining __BUILTIN_CPU_SUPPORTS__ had to be moved since the
preceeding lines aren't in GCC 6.
Given we have the macro __BUILTIN_CPU_SUPPORTS__, I could change the test to
use that instead of a dg-requires and drop ppc_cpu_supports_hw_available.
--
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meiss...@linux.vnet.ibm.com, phone: +1 (978) 899-4797
Index: gcc/config/rs6000/rs6000-c.c
===================================================================
--- gcc/config/rs6000/rs6000-c.c (revision 250169)
+++ gcc/config/rs6000/rs6000-c.c (working copy)
@@ -648,6 +648,9 @@ rs6000_cpu_cpp_builtins (cpp_reader *pfi
builtin_define ("__FLOAT128_HARDWARE__");
if (TARGET_LONG_DOUBLE_128 && FLOAT128_IBM_P (TFmode))
builtin_define ("__ibm128=long double");
+#ifdef TARGET_LIBC_PROVIDES_HWCAP_IN_TCB
+ builtin_define ("__BUILTIN_CPU_SUPPORTS__");
+#endif
/* We needed to create a keyword if -mfloat128-type was used but not -mfloat,
so we used __ieee128. If -mfloat128 was used, create a #define back to
Index: gcc/config/rs6000/rs6000.c
===================================================================
--- gcc/config/rs6000/rs6000.c (revision 250169)
+++ gcc/config/rs6000/rs6000.c (working copy)
@@ -15584,6 +15584,8 @@ cpu_expand_builtin (enum rs6000_builtins
emit_insn (gen_eqsi3 (scratch2, scratch1, const0_rtx));
emit_insn (gen_rtx_SET (target, gen_rtx_XOR (SImode, scratch2,
const1_rtx)));
}
+ else
+ gcc_unreachable ();
/* Record that we have expanded a CPU builtin, so that we can later
emit a reference to the special symbol exported by LIBC to ensure we
@@ -15591,6 +15593,9 @@ cpu_expand_builtin (enum rs6000_builtins
cpu_builtin_p = true;
#else
+ warning (0, "%s needs GLIBC (2.23 and newer) that exports hardware "
+ "capability bits", rs6000_builtin_info[(size_t) fcode].name);
+
/* For old LIBCs, always return FALSE. */
emit_move_insn (target, GEN_INT (0));
#endif /* TARGET_LIBC_PROVIDES_HWCAP_IN_TCB */
Index: gcc/doc/extend.texi
===================================================================
--- gcc/doc/extend.texi (revision 250169)
+++ gcc/doc/extend.texi (working copy)
@@ -14894,10 +14894,25 @@ This function is a @code{nop} on the Pow
to maintain API compatibility with the x86 builtins.
@end deftypefn
+@deftypefn {Built-in Function} void __builtin_cpu_init (void)
+This function is a @code{nop} on the PowerPC platform and is included solely
+to maintain API compatibility with the x86 builtins.
+@end deftypefn
+
@deftypefn {Built-in Function} int __builtin_cpu_is (const char *@var{cpuname})
This function returns a value of @code{1} if the run-time CPU is of type
-@var{cpuname} and returns @code{0} otherwise. The following CPU names can be
-detected:
+@var{cpuname} and returns @code{0} otherwise
+
+The @code{__builtin_cpu_is} function requires GLIBC 2.23 or newer
+which exports the hardware capability bits. GCC defines the macro
+@code{__BUILTIN_CPU_SUPPORTS__} if the @code{__builtin_cpu_supports}
+built-in function is fully supported.
+
+If GCC was configured to use a GLIBC before 2.23, the built-in
+function @code{__builtin_cpu_is} always returns a 0 and the compiler
+issues a warning.
+
+The following CPU names can be detected:
@table @samp
@item power9
@@ -14934,20 +14949,33 @@ IBM PowerPC Cell Broadband Engine Archit
Here is an example:
@smallexample
-if (__builtin_cpu_is ("power8"))
- @{
- do_power8 (); // POWER8 specific implementation.
- @}
-else
- @{
- do_generic (); // Generic implementation.
- @}
+#ifdef __BUILTIN_CPU_SUPPORTS__
+ if (__builtin_cpu_is ("power8"))
+ @{
+ do_power8 (); // POWER8 specific implementation.
+ @}
+ else
+#endif
+ @{
+ do_generic (); // Generic implementation.
+ @}
@end smallexample
@end deftypefn
@deftypefn {Built-in Function} int __builtin_cpu_supports (const char
*@var{feature})
This function returns a value of @code{1} if the run-time CPU supports the
HWCAP
-feature @var{feature} and returns @code{0} otherwise. The following features
can be
+feature @var{feature} and returns @code{0} otherwise.
+
+The @code{__builtin_cpu_supports} function requires GLIBC 2.23 or
+newer which exports the hardware capability bits. GCC defines the
+macro @code{__BUILTIN_CPU_SUPPORTS__} if the
+@code{__builtin_cpu_supports} built-in function is fully supported.
+
+If GCC was configured to use a GLIBC before 2.23, the built-in
+function @code{__builtin_cpu_suports} always returns a 0 and the
+compiler issues a warning.
+
+The following features can be
detected:
@table @samp
@@ -15031,14 +15059,16 @@ CPU supports the vector-scalar extension
Here is an example:
@smallexample
-if (__builtin_cpu_supports ("fpu"))
- @{
- asm("fadd %0,%1,%2" : "=d"(dst) : "d"(src1), "d"(src2));
- @}
-else
- @{
- dst = __fadd (src1, src2); // Software FP addition function.
- @}
+#ifdef __BUILTIN_CPU_SUPPORTS__
+ if (__builtin_cpu_supports ("fpu"))
+ @{
+ asm("fadd %0,%1,%2" : "=d"(dst) : "d"(src1), "d"(src2));
+ @}
+ else
+#endif
+ @{
+ dst = __fadd (src1, src2); // Software FP addition function.
+ @}
@end smallexample
@end deftypefn
Index: gcc/testsuite/lib/target-supports.exp
===================================================================
--- gcc/testsuite/lib/target-supports.exp (revision 250169)
+++ gcc/testsuite/lib/target-supports.exp (working copy)
@@ -1896,6 +1896,37 @@ proc check_effective_target_powerpc64_no
} {-O2}]
}
+# Return 1 if the target supports the __builtin_cpu_supports built-in,
+# including having a new enough library to support the test. Cache the result.
+# Require at least a power7 to run on.
+
+proc check_ppc_cpu_supports_hw_available { } {
+ return [check_cached_effective_target ppc_cpu_supports_hw_available {
+ # Some simulators are known to not support VSX/power8 instructions.
+ # For now, disable on Darwin
+ if { [istarget powerpc-*-eabi]
+ || [istarget powerpc*-*-eabispe]
+ || [istarget *-*-darwin*]} {
+ expr 0
+ } else {
+ set options "-mvsx"
+ check_runtime_nocache ppc_cpu_supports_hw_available {
+ int main()
+ {
+ #ifdef __MACH__
+ asm volatile ("xxlor vs0,vs0,vs0");
+ #else
+ asm volatile ("xxlor 0,0,0");
+ #endif
+ if (!__builtin_cpu_supports ("vsx"))
+ return 1;
+ return 0;
+ }
+ } $options
+ }
+ }]
+}
+
# Return 1 if the target supports executing power8 vector instructions, 0
# otherwise. Cache the result.
Index: gcc/testsuite/gcc.target/powerpc/cpu-builtin-1.c
===================================================================
--- gcc/testsuite/gcc.target/powerpc/cpu-builtin-1.c (revision 250169)
+++ gcc/testsuite/gcc.target/powerpc/cpu-builtin-1.c (working copy)
@@ -1,5 +1,6 @@
/* { dg-do compile { target { powerpc*-*-* } } } */
/* { dg-skip-if "" { powerpc*-*-darwin* } { "*" } { "" } } */
+/* { dg-require-effective-target ppc_cpu_supports_hw } */
void
use_cpu_is_builtins (unsigned int *p)
Index: gcc/config/rs6000/rs6000-c.c
===================================================================
--- gcc/config/rs6000/rs6000-c.c (revision 250186)
+++ gcc/config/rs6000/rs6000-c.c (working copy)
@@ -428,6 +428,9 @@ rs6000_cpu_cpp_builtins (cpp_reader *pfi
builtin_define ("__FLOAT128__");
if (TARGET_FLOAT128_HW)
builtin_define ("__FLOAT128_HARDWARE__");
+#ifdef TARGET_LIBC_PROVIDES_HWCAP_IN_TCB
+ builtin_define ("__BUILTIN_CPU_SUPPORTS__");
+#endif
if (TARGET_EXTRA_BUILTINS && cpp_get_options (pfile)->lang != CLK_ASM)
{
Index: gcc/config/rs6000/rs6000.c
===================================================================
--- gcc/config/rs6000/rs6000.c (revision 250186)
+++ gcc/config/rs6000/rs6000.c (working copy)
@@ -14162,6 +14162,8 @@ cpu_expand_builtin (enum rs6000_builtins
emit_insn (gen_eqsi3 (scratch2, scratch1, const0_rtx));
emit_insn (gen_rtx_SET (target, gen_rtx_XOR (SImode, scratch2,
const1_rtx)));
}
+ else
+ gcc_unreachable ();
/* Record that we have expanded a CPU builtin, so that we can later
emit a reference to the special symbol exported by LIBC to ensure we
@@ -14169,6 +14171,9 @@ cpu_expand_builtin (enum rs6000_builtins
cpu_builtin_p = true;
#else
+ warning (0, "%s needs GLIBC (2.23 and newer) that exports hardware "
+ "capability bits", rs6000_builtin_info[(size_t) fcode].name);
+
/* For old LIBCs, always return FALSE. */
emit_move_insn (target, GEN_INT (0));
#endif /* TARGET_LIBC_PROVIDES_HWCAP_IN_TCB */
Index: gcc/doc/extend.texi
===================================================================
--- gcc/doc/extend.texi (revision 250186)
+++ gcc/doc/extend.texi (working copy)
@@ -13667,10 +13667,25 @@ This function is a @code{nop} on the Pow
to maintain API compatibility with the x86 builtins.
@end deftypefn
+@deftypefn {Built-in Function} void __builtin_cpu_init (void)
+This function is a @code{nop} on the PowerPC platform and is included solely
+to maintain API compatibility with the x86 builtins.
+@end deftypefn
+
@deftypefn {Built-in Function} int __builtin_cpu_is (const char *@var{cpuname})
This function returns a value of @code{1} if the run-time CPU is of type
-@var{cpuname} and returns @code{0} otherwise. The following CPU names can be
-detected:
+@var{cpuname} and returns @code{0} otherwise
+
+The @code{__builtin_cpu_is} function requires GLIBC 2.23 or newer
+which exports the hardware capability bits. GCC defines the macro
+@code{__BUILTIN_CPU_SUPPORTS__} if the @code{__builtin_cpu_supports}
+built-in function is fully supported.
+
+If GCC was configured to use a GLIBC before 2.23, the built-in
+function @code{__builtin_cpu_is} always returns a 0 and the compiler
+issues a warning.
+
+The following CPU names can be detected:
@table @samp
@item power9
@@ -13707,20 +13722,33 @@ IBM PowerPC Cell Broadband Engine Archit
Here is an example:
@smallexample
-if (__builtin_cpu_is ("power8"))
- @{
- do_power8 (); // POWER8 specific implementation.
- @}
-else
- @{
- do_generic (); // Generic implementation.
- @}
+#ifdef __BUILTIN_CPU_SUPPORTS__
+ if (__builtin_cpu_is ("power8"))
+ @{
+ do_power8 (); // POWER8 specific implementation.
+ @}
+ else
+#endif
+ @{
+ do_generic (); // Generic implementation.
+ @}
@end smallexample
@end deftypefn
@deftypefn {Built-in Function} int __builtin_cpu_supports (const char
*@var{feature})
This function returns a value of @code{1} if the run-time CPU supports the
HWCAP
-feature @var{feature} and returns @code{0} otherwise. The following features
can be
+feature @var{feature} and returns @code{0} otherwise.
+
+The @code{__builtin_cpu_supports} function requires GLIBC 2.23 or
+newer which exports the hardware capability bits. GCC defines the
+macro @code{__BUILTIN_CPU_SUPPORTS__} if the
+@code{__builtin_cpu_supports} built-in function is fully supported.
+
+If GCC was configured to use a GLIBC before 2.23, the built-in
+function @code{__builtin_cpu_suports} always returns a 0 and the
+compiler issues a warning.
+
+The following features can be
detected:
@table @samp
@@ -13804,14 +13832,16 @@ CPU supports the vector-scalar extension
Here is an example:
@smallexample
-if (__builtin_cpu_supports ("fpu"))
- @{
- asm("fadd %0,%1,%2" : "=d"(dst) : "d"(src1), "d"(src2));
- @}
-else
- @{
- dst = __fadd (src1, src2); // Software FP addition function.
- @}
+#ifdef __BUILTIN_CPU_SUPPORTS__
+ if (__builtin_cpu_supports ("fpu"))
+ @{
+ asm("fadd %0,%1,%2" : "=d"(dst) : "d"(src1), "d"(src2));
+ @}
+ else
+#endif
+ @{
+ dst = __fadd (src1, src2); // Software FP addition function.
+ @}
@end smallexample
@end deftypefn
Index: gcc/testsuite/lib/target-supports.exp
===================================================================
--- gcc/testsuite/lib/target-supports.exp (revision 250186)
+++ gcc/testsuite/lib/target-supports.exp (working copy)
@@ -1648,6 +1648,37 @@ proc check_effective_target_powerpc64_no
} {-O2}]
}
+# Return 1 if the target supports the __builtin_cpu_supports built-in,
+# including having a new enough library to support the test. Cache the result.
+# Require at least a power7 to run on.
+
+proc check_ppc_cpu_supports_hw_available { } {
+ return [check_cached_effective_target ppc_cpu_supports_hw_available {
+ # Some simulators are known to not support VSX/power8 instructions.
+ # For now, disable on Darwin
+ if { [istarget powerpc-*-eabi]
+ || [istarget powerpc*-*-eabispe]
+ || [istarget *-*-darwin*]} {
+ expr 0
+ } else {
+ set options "-mvsx"
+ check_runtime_nocache ppc_cpu_supports_hw_available {
+ int main()
+ {
+ #ifdef __MACH__
+ asm volatile ("xxlor vs0,vs0,vs0");
+ #else
+ asm volatile ("xxlor 0,0,0");
+ #endif
+ if (!__builtin_cpu_supports ("vsx"))
+ return 1;
+ return 0;
+ }
+ } $options
+ }
+ }]
+}
+
# Return 1 if the target supports executing power8 vector instructions, 0
# otherwise. Cache the result.
Index: gcc/testsuite/gcc.target/powerpc/cpu-builtin-1.c
===================================================================
--- gcc/testsuite/gcc.target/powerpc/cpu-builtin-1.c (revision 250186)
+++ gcc/testsuite/gcc.target/powerpc/cpu-builtin-1.c (working copy)
@@ -1,5 +1,6 @@
/* { dg-do compile { target { powerpc*-*-* } } } */
/* { dg-skip-if "" { powerpc*-*-darwin* } { "*" } { "" } } */
+/* { dg-require-effective-target ppc_cpu_supports_hw } */
void
use_cpu_is_builtins (unsigned int *p)
