[PATCH] gdb: riscv_scan_prologue: handle LD instruction

[Lancelot SIX]

> 
> Would you be willing to add support for LW?  I think the test cold be
> adapted to cover both cases pretty easily, more below...

Yes, I’ll try to do that shortly.
> 
> > +	addi	sp,sp,-32
> > +	lla	t3,__canary  # Load the fake canary address.
> > +	ld	t4,0(t3)     # Load the canary.
> 
> As we don't actually check the canary anywhere (unless I'm missing
> something), then you could just add an extra:

You are right. In this test I only reproduce the installation of the
canary. I did not install an epilogue that checks for its value since
has no use in the context of this test.

> 
>   lw	t4,0(t3)
> 
> here before the ld, and then both cases will be covered.  Adding the
> support for this in GDB should be easy enough (based on SW/SD).
> 
> What do you think?

As you point out, the test can easily modified to incorporate a LW
instruction to cover both cases.  If I use other registers than T3/T4, I
can also test for C.LD / C.LW (the corresponding instructions from the
compressed instruction set).  I did test my implementation against C.LD
but did not include it in the testcase to keep it simple.  If I add a LW
I can as well test the 4 instructions (to be more precise, I test that
GDB can scan the prologue past those instructions, I never test what GDB
thinks those instructions do).

Best,
Lancelot.

> 
> Thanks,
> Andrew