From: Meng Zhuo <mzh@mzh.io>
To: musl@lists.openwall.com
Subject: [musl] [PATCH v3] math: add riscv64 round/roundf
Date: Wed, 12 Jun 2024 23:31:05 +0800 [thread overview]
Message-ID: <20240612153105.335451-1-mzh@mzh.io> (raw)
---
v2 -> v3:
* use x + x to check +-inf and NaN
---
v1 -> v2:
* drop ±inf check and use fabs as Rich suggested
---
src/math/riscv64/round.c | 21 +++++++++++++++++++++
src/math/riscv64/roundf.c | 21 +++++++++++++++++++++
2 files changed, 42 insertions(+)
create mode 100644 src/math/riscv64/round.c
create mode 100644 src/math/riscv64/roundf.c
diff --git a/src/math/riscv64/round.c b/src/math/riscv64/round.c
new file mode 100644
index 00000000..28d05aed
--- /dev/null
+++ b/src/math/riscv64/round.c
@@ -0,0 +1,21 @@
+#include <math.h>
+
+#if __riscv_flen >= 64
+
+double round(double x)
+{
+ if (isnan(x + x)) return x; // if x is +-inf or nan
+ if (fabs(x) >= 0x1p54) return x;
+ double tmp;
+ long long n;
+ __asm__ ("fcvt.l.d %0, %1, rmm" : "=r"(n) : "f"(x));
+ __asm__ ("fcvt.d.l %0, %1" : "=f"(tmp) : "r"(n));
+ __asm__ ("fsgnj.d %0, %1, %2" : "=f"(x) : "f"(tmp), "f"(x));
+ return x;
+}
+
+#else
+
+#include "../round.c"
+
+#endif
diff --git a/src/math/riscv64/roundf.c b/src/math/riscv64/roundf.c
new file mode 100644
index 00000000..a42b00d9
--- /dev/null
+++ b/src/math/riscv64/roundf.c
@@ -0,0 +1,21 @@
+#include <math.h>
+
+#if __riscv_flen >= 32
+
+float roundf(float x)
+{
+ if (isnan(x + x)) return x;
+ if (fabsf(x) >= 0x1p25) return x;
+ float tmp;
+ long n;
+ __asm__ ("fcvt.w.s %0, %1, rmm" : "=r"(n) : "f"(x));
+ __asm__ ("fcvt.s.w %0, %1" : "=f"(tmp) : "r"(n));
+ __asm__ ("fsgnj.s %0, %1, %2" : "=f"(x) : "f"(tmp), "f"(x));
+ return x;
+}
+
+#else
+
+#include "../roundf.c"
+
+#endif
--
2.39.2
next reply other threads:[~2024-06-12 15:31 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-12 15:31 Meng Zhuo [this message]
2024-06-12 15:44 ` Rich Felker
2024-06-12 16:06 Meng Zhuo
2024-06-12 16:50 ` Szabolcs Nagy
2024-06-12 16:54 ` Szabolcs Nagy
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240612153105.335451-1-mzh@mzh.io \
--to=mzh@mzh.io \
--cc=musl@lists.openwall.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/musl/
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).