cores
/
microwatt
mirror of https://github.com/antonblanchard/microwatt
3
1
Fork 1
Code Issues Projects Releases Wiki Activity
265 Commits
39 Branches
0 Tags
66 MiB
master
caravel-mpw7-20221125
caravel-mpw7-20220822
branch-alias
trace-test
gitignore
litedram-update
liteeth-update
fix-sdcard
fpu-init
loadstore-init
core_debug-init
icache-unused-sig
icache-insn-u-state
dcache-unused-sig
unused-sig
divider-init
loadstore-pmu-init
icache-pmu-events
fpu-typo
less-fpga-init
caravel-mpw6-20220530
caravel-mpw5-20220323
caravel-mpw5-20220322
alt-reset-address
log2ceil-issue
fpu-constant
asic-3
boxarty-20211011
icbi-issue
orange-crab-freq
dcache-nc-fix
remove-potato-uart
cache-tlb-parameters-2
caravel-20210114
caravel-20210105
jtag-port-2
jtag-port
nia-debug
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'd5346d0abf'
${ noResults }
Commit Graph

2 Commits (d5346d0abf6fdae7ac55706c3be43984ff6df3a8)

Author SHA1 Message Date
Anton Blanchard 1b559aee31 Fix count-leading/trailing-zeroes 
The current code simulates correctly, but produces miscompares when synthesized
onto an FPGA. On closer inspection GHDL synthesis complains about inferred
latches and there does seem to be issues.

Convert it to variables that are always initialized to zero at the start of the
process.

Fixes: 24a4a796ce ("execute: Consolidate count-leading/trailing-zeroes implementations")
Signed-off-by: Anton Blanchard <anton@linux.ibm.com>
 5 years ago
Paul Mackerras 24a4a796ce execute: Consolidate count-leading/trailing-zeroes implementations 
This adds combinatorial logic that does 32-bit and 64-bit count
leading and trailing zeroes in one unit, and consolidates the
four instructions under a single OP_CNTZ opcode.

This saves 84 slice LUTs on the Arty A7-100.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
 5 years ago