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SubjectRe: [PATCH v2] x86: insn: Add insn_is_fpu()
On Thu, Apr 09, 2020 at 01:09:11AM +0900, Masami Hiramatsu wrote:
> Add insn_is_fpu(insn) which tells that the insn is
> whether touch the FPU/SSE/MMX register or the instruction
> of FP coprocessor.
>
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---

Sadly, it turns out I need "FWAIT" too, which I tried adding like the
below, but that comes apart most mighty :/

The trouble is that FWAIT doesn't take a MODRM, so the previous
assumption that INAT_FPU implied INAT_MODRM needs to be broken, and I
think that ripples through somewhere.

(also, your patch adds some whitespace to convert_operands(), not sure
that was intended)

--- a/arch/x86/lib/x86-opcode-map.txt
+++ b/arch/x86/lib/x86-opcode-map.txt
@@ -206,7 +206,7 @@ Table: one byte opcode
98: CBW/CWDE/CDQE
99: CWD/CDQ/CQO
9a: CALLF Ap (i64)
-9b: FWAIT/WAIT
+9b: FWAIT/WAIT {FPU}
9c: PUSHF/D/Q Fv (d64)
9d: POPF/D/Q Fv (d64)
9e: SAHF
--- a/arch/x86/tools/gen-insn-attr-x86.awk
+++ b/arch/x86/tools/gen-insn-attr-x86.awk
@@ -331,9 +331,13 @@ function convert_operands(count,opnd,
if (match(opcode, rex_expr))
flags = add_flags(flags, "INAT_MAKE_PREFIX(INAT_PFX_REX)")

+ # check coprocessor escape
+ if (match(ext, "^ESC"))
+ flags = add_flags(flags, "INAT_MODRM")
+
# check FPU/MMX/SSE superscripts
if (match(ext, fpu_expr))
- flags = add_flags(flags, "INAT_MODRM | INAT_FPU")
+ flags = add_flags(flags, "INAT_FPU")

# check VEX codes
if (match(ext, evexonly_expr))
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