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[Bug gas/22871] Encode instructions of 64-bit registers without the REX_
From: |
hjl.tools at gmail dot com |
Subject: |
[Bug gas/22871] Encode instructions of 64-bit registers without the REX_W bit |
Date: |
Wed, 21 Feb 2018 13:43:02 +0000 |
https://sourceware.org/bugzilla/show_bug.cgi?id=22871
--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Jan Beulich from comment #1)
> subq %r64, %r64 and testq $imm31, %r64 could similarly benefit. Whether
I added subq and testq to users/hjl/optimize branch at
https://github.com/hjl-tools/binutils-gdb/tree/users/hjl/optimize
> converting test{q,l,w} $imm8,%r{64,32,16} to testb $imm8,%r8 isn't as clear,
> but I think reads of 8-bit registers are commonly not causing stalls (only
> writes do).
>
> Along those lines test{q,l,w} $imm,mem might allow conversion if all set
> bits in imm fall within a single byte. Of course care needs to be taken that
> the adjustment to the displacement won't break addressability of the object.
Let's go with 64-bit register cases first and see how they go.
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- [Bug gas/22871] New: Encode instructions of 64-bit registers without the REX_W bit, hjl.tools at gmail dot com, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit registers without the REX_W bit, hjl.tools at gmail dot com, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit registers without the REX_W bit, jbeulich at novell dot com, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit registers without the REX_W bit,
hjl.tools at gmail dot com <=
- [Bug gas/22871] Encode instructions of 64-bit registers without the REX_W bit, hjl.tools at gmail dot com, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, hjl.tools at gmail dot com, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, address@hidden, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, hjl.tools at gmail dot com, 2018/02/21
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, jbeulich at novell dot com, 2018/02/22
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, hjl.tools at gmail dot com, 2018/02/22
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, hjl.tools at gmail dot com, 2018/02/22
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, address@hidden, 2018/02/22
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, address@hidden, 2018/02/22
- [Bug gas/22871] Encode instructions of 64-bit operand without the REX_W bit, hjl.tools at gmail dot com, 2018/02/22