From e99939491820df300a6179719d807f810e7f1680 Mon Sep 17 00:00:00 2001
From: uvok
Date: Thu, 22 Jan 2026 20:46:11 +0100
Subject: eater: PC inc included, decode on negedge

Some cycles can be saved.
As previously (wrongly) committed, the PC can be incremented early,
but the decoder needs to do this "early", so as now implemented,
on the falling clock adge already.
---
 eater_cpu/eater_computer.sv | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

(limited to 'eater_cpu/eater_computer.sv')

diff --git a/eater_cpu/eater_computer.sv b/eater_cpu/eater_computer.sv
index 6569831..2fca29e 100644
--- a/eater_cpu/eater_computer.sv
+++ b/eater_cpu/eater_computer.sv
@@ -167,8 +167,11 @@ eater_register OUT (
   .always_out(OUT_out)
 );
 
+// run decoder on negated clock,
+// allowing stuff to be clocked in "early"
+wire DEC_clk_neg = ~clk_in;
 eater_decoder decoder (
-  .clk_i(clk_in),
+  .clk_i(DEC_clk_neg),
   .instruction_i(INS_out),
   .flags_o(automatic_flags)
 );
-- 
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