diff mbox series

[nvptx] Update nvptx's bitrev<mode>2 pattern to use BITREVERSE rtx.

Message ID 00a701d99995$0c8d3d60$25a7b820$@nextmovesoftware.com
State Committed
Headers
Series [nvptx] Update nvptx's bitrev<mode>2 pattern to use BITREVERSE rtx. |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_gcc_build--master-arm success Testing passed
linaro-tcwg-bot/tcwg_gcc_build--master-aarch64 success Testing passed
linaro-tcwg-bot/tcwg_gcc_check--master-arm success Testing passed

Commit Message

Roger Sayle June 7, 2023, 11:09 p.m. UTC 
  This minor tweak to the nvptx backend switches the representation of
of the brev instruction from an UNSPEC to instead use the new BITREVERSE
rtx.  This allows various RTL optimizations including evaluation (constant
folding) of integer constant arguments at compile-time.

This patch has been tested on nvptx-none with make and make -k check
with no new failures.  Ok for mainline?


2023-06-07  Roger Sayle  <roger@nextmovesoftware.com>

gcc/ChangeLog
        * config/nvptx/nvptx.md (UNSPEC_BITREV): Delete.
        (bitrev<mode>2): Represent using bitreverse.


Thanks in advance,
Roger
--

Comments

Thomas Schwinge Nov. 15, 2023, 2:33 p.m. UTC | #1 
Hi!

On 2023-06-08T00:09:00+0100, "Roger Sayle" <roger@nextmovesoftware.com> wrote:
> This minor tweak to the nvptx backend switches the representation of
> of the brev instruction from an UNSPEC to instead use the new BITREVERSE
> rtx.

ACK.

> This allows various RTL optimizations including evaluation (constant
> folding) of integer constant arguments at compile-time.

..., which we're then observing via
commit 61c45c055a5ccfc59463c21ab057dece822d973c
"nvptx: Extend 'brev' test cases" that I just pushed;
<https://inbox.sourceware.org/87a5rfum3v.fsf@euler.schwinge.homeip.net>
"nvptx: Extend 'brev' test cases".

> This patch has been tested on nvptx-none with make and make -k check
> with no new failures.  Ok for mainline?

I've thus updated the test cases for these changes here, and pushed to
master branch commit 75c20a99b3a242121eef8a532f5224c00c471b56
"Update nvptx's bitrev<mode>2 pattern to use BITREVERSE rtx.", see
attached.


Grüße
 Thomas


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diff mbox series

Patch

diff --git a/gcc/config/nvptx/nvptx.md b/gcc/config/nvptx/nvptx.md
index 1bb9304..7a7c994 100644
--- a/gcc/config/nvptx/nvptx.md
+++ b/gcc/config/nvptx/nvptx.md
@@ -34,8 +34,6 @@ 
    UNSPEC_FPINT_CEIL
    UNSPEC_FPINT_NEARBYINT
 
-   UNSPEC_BITREV
-
    UNSPEC_ALLOCA
 
    UNSPEC_SET_SOFTSTACK
@@ -636,8 +634,7 @@ 
 
 (define_insn "bitrev<mode>2"
   [(set (match_operand:SDIM 0 "nvptx_register_operand" "=R")
-	(unspec:SDIM [(match_operand:SDIM 1 "nvptx_register_operand" "R")]
-		     UNSPEC_BITREV))]
+	(bitreverse:SDIM (match_operand:SDIM 1 "nvptx_register_operand" "R")))]
   ""
   "%.\\tbrev.b%T0\\t%0, %1;")