From: Christophe Lyon <christophe.lyon@st.com>
To: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Subject: [Qemu-devel] [PATCH] Support saturation with shift=0.
Date: Wed, 19 Jan 2011 17:10:52 +0100 [thread overview]
Message-ID: <4D370D0C.5040706@st.com> (raw)
This patch fixes corner-case saturations, when the target range is
zero. It merely removes the guard against (sh == 0), and makes:
__ssat(0x87654321, 1) return 0xffffffff and set the saturation flag
__usat(0x87654321, 0) return 0 and set the saturation flag
Signed-off-by: Christophe Lyon <christophe.lyon@st.com>
---
target-arm/translate.c | 28 ++++++++++++----------------
1 files changed, 12 insertions(+), 16 deletions(-)
diff --git a/target-arm/translate.c b/target-arm/translate.c
index 721bada..41cbb96 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -6896,27 +6896,23 @@ static void disas_arm_insn(CPUState * env, DisasContext *s)
tcg_gen_shli_i32(tmp, tmp, shift);
}
sh = (insn >> 16) & 0x1f;
- if (sh != 0) {
- tmp2 = tcg_const_i32(sh);
- if (insn & (1 << 22))
- gen_helper_usat(tmp, tmp, tmp2);
- else
- gen_helper_ssat(tmp, tmp, tmp2);
- tcg_temp_free_i32(tmp2);
- }
+ tmp2 = tcg_const_i32(sh);
+ if (insn & (1 << 22))
+ gen_helper_usat(tmp, tmp, tmp2);
+ else
+ gen_helper_ssat(tmp, tmp, tmp2);
+ tcg_temp_free_i32(tmp2);
store_reg(s, rd, tmp);
} else if ((insn & 0x00300fe0) == 0x00200f20) {
/* [us]sat16 */
tmp = load_reg(s, rm);
sh = (insn >> 16) & 0x1f;
- if (sh != 0) {
- tmp2 = tcg_const_i32(sh);
- if (insn & (1 << 22))
- gen_helper_usat16(tmp, tmp, tmp2);
- else
- gen_helper_ssat16(tmp, tmp, tmp2);
- tcg_temp_free_i32(tmp2);
- }
+ tmp2 = tcg_const_i32(sh);
+ if (insn & (1 << 22))
+ gen_helper_usat16(tmp, tmp, tmp2);
+ else
+ gen_helper_ssat16(tmp, tmp, tmp2);
+ tcg_temp_free_i32(tmp2);
store_reg(s, rd, tmp);
} else if ((insn & 0x00700fe0) == 0x00000fa0) {
/* Select bytes. */
--
1.7.2.3
next reply other threads:[~2011-01-19 16:11 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-19 16:10 Christophe Lyon [this message]
2011-01-19 16:51 ` [Qemu-devel] [PATCH] Support saturation with shift=0 Peter Maydell
2011-01-20 12:06 ` Christophe Lyon
2011-01-20 12:15 ` Peter Maydell
2011-01-26 13:33 ` Aurelien Jarno
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=4D370D0C.5040706@st.com \
--to=christophe.lyon@st.com \
--cc=qemu-devel@nongnu.org \
/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.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.