On Sun, 12 Aug 2012, Cyril Chemparathy wrote:
> On 08/11/12 22:35, Nicolas Pitre wrote:
> > On Fri, 10 Aug 2012, Cyril Chemparathy wrote:
> >
> > > This patch adds basic sanity tests to ensure that the instruction patching
> > > results in valid instruction encodings. This is done by verifying the
> > > output
> > > of the patch process against a vector of assembler generated instructions
> > > at
> > > init time.
> > >
> > > Signed-off-by: Cyril Chemparathy <cy...@ti.com>
> > > ---
> [...]
> > > + __asm__ __volatile__ (
> > > + " .irp shift1, 0, 6, 12, 18\n"
> > > + " .irp shift2, 0, 1, 2, 3, 4, 5\n"
> > > + " add r1, r2, #(0x41 << (\\shift1 + \\shift2))\n"
> > > + " .endr\n"
> > > + " .endr\n"
> >
> >
> > Maybe adding a "add r1, r2 #0x81 << 24" here might be a good thing since
> > this is the most used case but missing from the above.
> >
>
> Indeed. I've now replaced this with something a bit more extensive. Does the
> following look better?
>
> +struct patch_test_imm8 {
> + u16 imm;
> + u16 shift;
> + u32 insn;
> +};
> +
> +static void __init __used __naked __patch_test_code_imm8(void)
> +{
> + __asm__ __volatile__ (
> +
> + /* a single test case */
> + " .macro test_one, imm, sft\n"
> + " .hword \\imm\n"
> + " .hword \\sft\n"
> + " add r1, r2, #(\\imm << \\sft)\n"
> + " .endm\n"
> +
> + /* a sequence of tests at 'inc' increments of shift */
> + " .macro test_seq, imm, sft, max, inc\n"
> + " test_one \\imm, \\sft\n"
> + " .if \\sft < \\max\n"
> + " test_seq \\imm, (\\sft + \\inc), \\max,
> \\inc\n"
> + " .endif\n"
> + " .endm\n"
> +
> + /* an empty record to mark the end */
> + " .macro test_end\n"
> + " .hword 0, 0\n"
> + " .word 0\n"
> + " .endm\n"
> +
> + /* finally generate the test sequences */
> + " test_seq 0x41, 0, 24, 1\n"
> + " test_seq 0x81, 0, 24, 2\n"
> + " test_end\n"
> + : : :
> + );
> +}
Yes, this is certainly quite extensive. :-)
Nicolas
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