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| author | Adrian Hunter <adrian.hunter@intel.com> | 2024-05-02 13:58:50 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2024-05-02 14:13:45 +0300 |
| commit | 87bbaf1a4be4904fcf04a024e7c1d9f9d1fa945b (patch) | |
| tree | caefeb3858545b5ea88eacc72b98f6e812e0d531 /arch/x86/lib | |
| parent | 159039af8c074a14545fd695c38d2772b3c98b12 (diff) | |
| download | linux-87bbaf1a4be4904fcf04a024e7c1d9f9d1fa945b.tar.xz | |
x86/insn: Add support for APX EVEX to the instruction decoder logic
Intel Advanced Performance Extensions (APX) extends the EVEX prefix to
support:
- extended general purpose registers (EGPRs) i.e. r16 to r31
- Push-Pop Acceleration (PPX) hints
- new data destination (NDD) register
- suppress status flags writes (NF) of common instructions
- new instructions
Refer to the Intel Advanced Performance Extensions (Intel APX) Architecture
Specification for details.
The extended EVEX prefix does not need amended instruction decoder logic,
except in one area. Some instructions are defined as SCALABLE which means
the EVEX.W bit and EVEX.pp bits are used to determine operand size.
Specifically, if an instruction is SCALABLE and EVEX.W is zero, then
EVEX.pp value 0 (representing no prefix NP) means default operand size,
whereas EVEX.pp value 1 (representing 66 prefix) means operand size
override i.e. 16 bits
Add an attribute (INAT_EVEX_SCALABLE) to identify such instructions, and
amend the logic appropriately.
Amend the awk script that generates the attribute tables from the opcode
map, to recognise "(es)" as attribute INAT_EVEX_SCALABLE.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240502105853.5338-8-adrian.hunter@intel.com
Diffstat (limited to 'arch/x86/lib')
| -rw-r--r-- | arch/x86/lib/insn.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c index 6126ddc6e5f5..5952ab41c60f 100644 --- a/arch/x86/lib/insn.c +++ b/arch/x86/lib/insn.c @@ -294,6 +294,10 @@ int insn_get_opcode(struct insn *insn) m = insn_vex_m_bits(insn); p = insn_vex_p_bits(insn); insn->attr = inat_get_avx_attribute(op, m, p); + /* SCALABLE EVEX uses p bits to encode operand size */ + if (inat_evex_scalable(insn->attr) && !insn_vex_w_bit(insn) && + p == INAT_PFX_OPNDSZ) + insn->opnd_bytes = 2; if ((inat_must_evex(insn->attr) && !insn_is_evex(insn)) || (!inat_accept_vex(insn->attr) && !inat_is_group(insn->attr))) { |