From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Subject: [PATCH v2 0/5] tcg/i386: Improve vector shifts
Date: Sat, 30 Aug 2025 13:39:21 +1000 [thread overview]
Message-ID: <20250830033926.372955-1-richard.henderson@linaro.org> (raw)
x86 doesn't directly support 8-bit vector shifts, so we have
some 2 to 5 insn expansions. With VGF2P8AFFINEQB, we can do
it in 1 insn, plus a (possibly shared) constant load.
Changes for v2:
- Use PCMPGT for arithmetic right-shift of bits-1 (paolo).
- Tidy an instance of non-canonical operand ordering.
r~
Richard Henderson (5):
cpuinfo/i386: Detect GFNI as an AVX extension
tcg/i386: Expand sari of bits-1 as pcmpgt
tcg/i386: Use canonical operand ordering in expand_vec_sari
tcg/i386: Add INDEX_op_x86_vgf2p8affineqb_vec
tcg/i386: Use vgf2p8affineqb for MO_8 vector shifts
host/include/i386/host/cpuinfo.h | 1 +
include/qemu/cpuid.h | 3 ++
util/cpuinfo-i386.c | 1 +
tcg/i386/tcg-target-opc.h.inc | 1 +
tcg/i386/tcg-target.c.inc | 91 +++++++++++++++++++++++++++++---
5 files changed, 91 insertions(+), 6 deletions(-)
--
2.43.0
next reply other threads:[~2025-08-30 16:20 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-30 3:39 Richard Henderson [this message]
2025-08-30 3:39 ` [PATCH v2 1/5] cpuinfo/i386: Detect GFNI as an AVX extension Richard Henderson
2025-08-30 3:39 ` [PATCH v2 2/5] tcg/i386: Expand sari of bits-1 as pcmpgt Richard Henderson
2025-08-30 3:39 ` [PATCH v2 3/5] tcg/i386: Use canonical operand ordering in expand_vec_sari Richard Henderson
2025-09-01 6:44 ` Philippe Mathieu-Daudé
2025-09-02 13:28 ` Richard Henderson
2025-08-30 3:39 ` [PATCH v2 4/5] tcg/i386: Add INDEX_op_x86_vgf2p8affineqb_vec Richard Henderson
2025-08-30 3:39 ` [PATCH v2 5/5] tcg/i386: Use vgf2p8affineqb for MO_8 vector shifts Richard Henderson
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