From 57ca51be76ec4dc6eba802728ca6407520c704e4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marcelina=20Ko=C5=9Bcielnicka?= Date: Wed, 26 May 2021 02:06:44 +0200 Subject: kernel/mem: Add prepare_wr_merge helper. --- kernel/mem.cc | 20 ++++++++++++++++++++ kernel/mem.h | 7 +++++++ 2 files changed, 27 insertions(+) diff --git a/kernel/mem.cc b/kernel/mem.cc index fe88be5d7..77165d97f 100644 --- a/kernel/mem.cc +++ b/kernel/mem.cc @@ -786,3 +786,23 @@ void Mem::emulate_priority(int idx1, int idx2) } port2.priority_mask[idx1] = false; } + +void Mem::prepare_wr_merge(int idx1, int idx2) { + log_assert(idx1 < idx2); + auto &port1 = wr_ports[idx1]; + auto &port2 = wr_ports[idx2]; + // If port 2 has priority over a port before port 1, make port 1 have priority too. + for (int i = 0; i < idx1; i++) + if (port2.priority_mask[i]) + port1.priority_mask[i] = true; + // If port 2 has priority over a port after port 1, emulate it. + for (int i = idx1 + 1; i < idx2; i++) + if (port2.priority_mask[i]) + emulate_priority(i, idx2); + // If some port had priority over port 2, make it have priority over the merged port too. + for (int i = idx2 + 1; i < GetSize(wr_ports); i++) { + auto &oport = wr_ports[i]; + if (oport.priority_mask[idx2]) + oport.priority_mask[idx1] = true; + } +} diff --git a/kernel/mem.h b/kernel/mem.h index 49b72bc35..15886877a 100644 --- a/kernel/mem.h +++ b/kernel/mem.h @@ -84,6 +84,13 @@ struct Mem { // from the priority mask. void emulate_priority(int idx1, int idx2); + // Prepares for merging write port idx2 into idx1 (where idx1 < idx2). + // Specifically, takes care of priority masks: any priority relations + // that idx2 had are replicated onto idx1, unless they conflict with + // priorities already present on idx1, in which case emulate_priority + // is called. + void prepare_wr_merge(int idx1, int idx2); + Mem(Module *module, IdString memid, int width, int start_offset, int size) : module(module), memid(memid), packed(false), mem(nullptr), cell(nullptr), width(width), start_offset(start_offset), size(size) {} }; -- cgit v1.2.3