Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

On Thu, Jan 13, 2022 at 6:28 PM Philipp Tomsich wrote: > > On Thu, 13 Jan 2022 at 06:07, Alistair Francis wrote: > > > > On Thu, Jan 13, 2022 at 1:42 AM Philipp Tomsich > > wrote: > > > > > > Alistair, > > > > > > Do you (and the other RISC-V custodians of target/riscv) have any opinion > > > o

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

On Thu, 13 Jan 2022 at 06:07, Alistair Francis wrote: > > On Thu, Jan 13, 2022 at 1:42 AM Philipp Tomsich > wrote: > > > > Alistair, > > > > Do you (and the other RISC-V custodians of target/riscv) have any opinion > > on this? > > We can go either way — and it boils down to a style and process

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

On Thu, Jan 13, 2022 at 1:42 AM Philipp Tomsich wrote: > > Alistair, > > Do you (and the other RISC-V custodians of target/riscv) have any opinion on > this? > We can go either way — and it boils down to a style and process question. Sorry, it's a busy week! I had a quick look over this series

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

Alistair, Do you (and the other RISC-V custodians of target/riscv) have any opinion on this? We can go either way — and it boils down to a style and process question. Thanks, Philipp. On Mon, 10 Jan 2022 at 12:30, Philippe Mathieu-Daudé wrote: > On 1/10/22 12:11, Philipp Tomsich wrote: > > On

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

On 1/10/22 12:11, Philipp Tomsich wrote: > On Mon, 10 Jan 2022 at 11:03, Philippe Mathieu-Daudé > wrote: > > On 1/10/22 10:52, Philipp Tomsich wrote: > > For RISC-V the opcode decode will change between different vendor > > implementations of RISC-V (emulated b

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

On Mon, 10 Jan 2022 at 11:03, Philippe Mathieu-Daudé wrote: > On 1/10/22 10:52, Philipp Tomsich wrote: > > For RISC-V the opcode decode will change between different vendor > > implementations of RISC-V (emulated by the same qemu binary). > > Any two vendors may reuse the same opcode space, e.g.,

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

On 1/10/22 10:52, Philipp Tomsich wrote: > For RISC-V the opcode decode will change between different vendor > implementations of RISC-V (emulated by the same qemu binary). > Any two vendors may reuse the same opcode space, e.g., we may end up with: > > # *** RV64 Custom-3 Extension *** > { > vt

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

Philippe, Assuming that we move into this direction for the vendor-extensions, I would like to also see some of the other conditionally available extensions in RISC-V to move to predicated decode (which would move this mechanism past overlapping multi-patterns). E.g., we have the following clumsi

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

For RISC-V the opcode decode will change between different vendor implementations of RISC-V (emulated by the same qemu binary). Any two vendors may reuse the same opcode space, e.g., we may end up with: # *** RV64 Custom-3 Extension *** { vt_maskc 000 . . 110 . 011 @r |has

Re: [PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

Hi Philipp, On 1/9/22 21:56, Philipp Tomsich wrote: > This adds the possibility to specify a predicate-function that is > called as part of decoding in multi-patterns; it is intended for > use-cases (such as vendor-defined instructions in RISC-V) where the > same bitpattern may decode into differe

[PATCH v1 1/2] decodetree: Add an optional predicate-function for decoding

This adds the possibility to specify a predicate-function that is called as part of decoding in multi-patterns; it is intended for use-cases (such as vendor-defined instructions in RISC-V) where the same bitpattern may decode into different functions depending on the overall configuration of the em