diff mbox series

[v2,5/5] riscv: add vectorized __memcmpeq

Message ID 20230421073412.14355-1-hau.hsu@sifive.com
State Dropped
Headers
Series None |

Commit Message

Hau Hsu April 21, 2023, 7:34 a.m. UTC 
  From: Yun Hsiang <yun.hsiang@sifive.com>

This patch proposes implementations of __memcmpeq that leverage the
RISC-V V extension (RVV), version 1.0. These routines assumes VLEN is at
least 32 bits, as is required by all currently defined vector
extensions, and they support arbitrarily large VLEN. All implementations
work for both RV32 and RV64 platforms, and make no assumptions about
page size.
---
 sysdeps/riscv/rvv/memcmp.S   |  4 ---
 sysdeps/riscv/rvv/memcmpeq.S | 69 ++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+), 4 deletions(-)
 create mode 100644 sysdeps/riscv/rvv/memcmpeq.S
diff mbox series

Patch

diff --git a/sysdeps/riscv/rvv/memcmp.S b/sysdeps/riscv/rvv/memcmp.S
index b156ec524c..74d8361293 100644
--- a/sysdeps/riscv/rvv/memcmp.S
+++ b/sysdeps/riscv/rvv/memcmp.S
@@ -69,7 +69,3 @@  L(found):
 
 END(memcmp)
 libc_hidden_builtin_def (memcmp)
-weak_alias (memcmp,bcmp)
-strong_alias (memcmp, __memcmpeq)
-libc_hidden_def (__memcmpeq)
-
diff --git a/sysdeps/riscv/rvv/memcmpeq.S b/sysdeps/riscv/rvv/memcmpeq.S
new file mode 100644
index 0000000000..302bca6992
--- /dev/null
+++ b/sysdeps/riscv/rvv/memcmpeq.S
@@ -0,0 +1,69 @@ 
+/* RVV versions memcmp.  RISC-V version.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jerry Shih <jerry.shih@sifive.com>,
+                  Yun Hsiang <yun.hsiang@sifive.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include <sys/asm.h>
+
+
+#define iResult a0
+
+#define pSrc1 a0
+#define pSrc2 a1
+#define iNum a2
+
+#define iVL a3
+#define iTemp a4
+
+#define ELEM_LMUL_SETTING m1
+#define vData1 v0
+#define vData2 v8
+#define vMask v16
+
+ENTRY(__memcmpeq)
+
+L(loop):
+    vsetvli iVL, iNum, e8, ELEM_LMUL_SETTING, ta, ma
+
+    vle8.v vData1, (pSrc1)
+    vle8.v vData2, (pSrc2)
+
+    vmsne.vv vMask, vData1, vData2
+    sub iNum, iNum, iVL
+    vfirst.m iTemp, vMask
+
+    // Skip the loop if we find the different value between pSrc1 and pSrc2.
+    bgez iTemp, L(found)
+
+    add pSrc1, pSrc1, iVL
+    add pSrc2, pSrc2, iVL
+
+    bnez iNum, L(loop)
+
+    li iResult, 0
+    ret
+
+L(found):
+    mv iResult, iVL
+    ret
+
+END(__memcmpeq)
+
+weak_alias (__memcmpeq, bcmp)
+libc_hidden_def (__memcmpeq)