https://gcc.gnu.org/g:64bfc5289d5a3f3f1a33bb1e35eb0e680364bb78
commit 64bfc5289d5a3f3f1a33bb1e35eb0e680364bb78
Author: Michael Meissner <meiss...@linux.ibm.com>
Date: Mon May 19 16:19:47 2025 -0400
Use vector pair load/store for memcpy with -mcpu=future
In the development for the power10 processor, GCC did not enable using the
load
vector pair and store vector pair instructions when optimizing things like
memory copy. This patch enables using those instructions if -mcpu=future is
used.
2025-05-19 Michael Meissner <meiss...@linux.ibm.com>
gcc/
* config/rs6000/rs6000-cpus.def (ISA_FUTURE_MASKS_SERVER): Enable
using
load vector pair and store vector pair instructions for memory copy
operations.
(POWERPC_MASKS): Make the bit for enabling using load vector pair
and
store vector pair operations set and reset when the PowerPC
processor is
changed.
* gcc/config/rs6000/rs6000.cc (rs6000_machine_from_flags): Disable
-mblock-ops-vector-pair from influcing .machine selection.
gcc/testsuite/
* gcc.target/powerpc/future-3.c: New test.
Diff:
---
gcc/config/rs6000/rs6000-cpus.def | 4 +++-
gcc/config/rs6000/rs6000.cc | 2 +-
gcc/testsuite/gcc.target/powerpc/future-3.c | 22 ++++++++++++++++++++++
3 files changed, 26 insertions(+), 2 deletions(-)
diff --git a/gcc/config/rs6000/rs6000-cpus.def
b/gcc/config/rs6000/rs6000-cpus.def
index 228d0b5e7b54..063591f5c094 100644
--- a/gcc/config/rs6000/rs6000-cpus.def
+++ b/gcc/config/rs6000/rs6000-cpus.def
@@ -84,7 +84,8 @@
| OPTION_MASK_POWER11)
#define FUTURE_MASKS_SERVER (POWER11_MASKS_SERVER \
- | OPTION_MASK_FUTURE)
+ | OPTION_MASK_FUTURE \
+ | OPTION_MASK_BLOCK_OPS_VECTOR_PAIR)
/* Flags that need to be turned off if -mno-vsx. */
#define OTHER_VSX_VECTOR_MASKS (OPTION_MASK_EFFICIENT_UNALIGNED_VSX \
@@ -114,6 +115,7 @@
/* Mask of all options to set the default isa flags based on -mcpu=<xxx>. */
#define POWERPC_MASKS (OPTION_MASK_ALTIVEC \
+ | OPTION_MASK_BLOCK_OPS_VECTOR_PAIR \
| OPTION_MASK_CMPB \
| OPTION_MASK_CRYPTO \
| OPTION_MASK_DFP \
diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
index f1de7a4c85a5..9d59990303d0 100644
--- a/gcc/config/rs6000/rs6000.cc
+++ b/gcc/config/rs6000/rs6000.cc
@@ -5908,7 +5908,7 @@ rs6000_machine_from_flags (void)
/* Disable the flags that should never influence the .machine selection. */
flags &= ~(OPTION_MASK_PPC_GFXOPT | OPTION_MASK_PPC_GPOPT | OPTION_MASK_ISEL
- | OPTION_MASK_ALTIVEC);
+ | OPTION_MASK_ALTIVEC | OPTION_MASK_BLOCK_OPS_VECTOR_PAIR);
if ((flags & (FUTURE_MASKS_SERVER & ~ISA_3_1_MASKS_SERVER)) != 0)
return "future";
diff --git a/gcc/testsuite/gcc.target/powerpc/future-3.c
b/gcc/testsuite/gcc.target/powerpc/future-3.c
new file mode 100644
index 000000000000..afa22228b96d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/future-3.c
@@ -0,0 +1,22 @@
+/* 32-bit doesn't generate vector pair instructions. */
+/* { dg-do compile { target lp64 } } */
+/* { dg-options "-mdejagnu-cpu=future -O2" } */
+
+/* Test to see that memcpy will use load/store vector pair with
+ -mcpu=future. */
+
+#ifndef SIZE
+#define SIZE 4
+#endif
+
+extern vector double to[SIZE], from[SIZE];
+
+void
+copy (void)
+{
+ __builtin_memcpy (to, from, sizeof (to));
+ return;
+}
+
+/* { dg-final { scan-assembler {\mlxvpx?\M} } } */
+/* { dg-final { scan-assembler {\mstxvpx?\M} } } */
