https://gcc.gnu.org/g:6dd96375a52b4c31118d5d9f5e7e228893599a46
commit 6dd96375a52b4c31118d5d9f5e7e228893599a46
Author: Michael Meissner <meiss...@linux.ibm.com>
Date: Thu Mar 27 19:06:43 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.
2025-03-27 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 4cea1775f110..011f67d290e9 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} } } */
