On Tue, Dec 08, 2020 at 03:18:54PM -0600, Richard Henderson wrote:
> As for modifying the fast path cases, the code is quite delicate,
> and you run into problems with live registers. Which could be
> worked around in each backend, but... why?
Perhaps thinking that working at IR level would preve
On 12/7/20 4:10 AM, Stephane Duverger wrote:
> This leads me to that simple reflection:
>
> If we want to filter on every memory accesses, *out of the fast-path*,
> the most natural place to do so would be in store_helper() and
> load_helper() from accel/tcg/cputlb.c. By doing so, every target wou
On Sat, Dec 05, 2020 at 06:38:25AM -0600, Richard Henderson wrote:
> The difference is that the slow path is aware that there are input registers
> that are live, containing data (addrlo, addrhi, datalo, datahi), which must be
> stored into the arguments for the slow path call. Those input registe
On 12/4/20 7:34 PM, Stephane Duverger wrote:
>> You can't just inject a call anywhere you like. If you add it at
>> the IR level, then the rest of the compiler will see it and work
>> properly. If you add the call in the middle of another operation,
>> the compiler doesn't get to see it and Bad T
On Fri, Dec 04, 2020 at 01:35:55PM -0600, Richard Henderson wrote:
Thank you Richard for your answer. I don't want to generate a debate,
or defend the way I've done things initially. Really want to clarify
these internals. Hope it will benefit to other QEMU enthusiasts.
> You can't just inject a
On 12/4/20 9:36 AM, Stephane Duverger wrote:
> Hello,
>
> While looking at tcg/i386/tcg-target.c.inc:tcg_out_qemu_st(), I
> discovered that the TCG generates a call to a store helper at the end
> of the TB which is executed on TLB miss and get back to the remaining
> translated ops. I tried to mim
Hello,
While looking at tcg/i386/tcg-target.c.inc:tcg_out_qemu_st(), I
discovered that the TCG generates a call to a store helper at the end
of the TB which is executed on TLB miss and get back to the remaining
translated ops. I tried to mimick this behavior around the fast path
(right between tcg
