From 15ef6084533809894dd0b5200a65497047c2ccf8 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Fri, 19 Aug 2016 19:48:26 +0200
Subject: Added memory_memx pass, "memory -memx", and "prep -memx"
---
passes/memory/Makefile.inc | 1 +
passes/memory/memory.cc | 13 ++++++-
passes/memory/memory_memx.cc | 92 ++++++++++++++++++++++++++++++++++++++++++++
techlibs/common/prep.cc | 19 ++++++++-
4 files changed, 121 insertions(+), 4 deletions(-)
create mode 100644 passes/memory/memory_memx.cc
diff --git a/passes/memory/Makefile.inc b/passes/memory/Makefile.inc
index aeff225d8..ad359c01b 100644
--- a/passes/memory/Makefile.inc
+++ b/passes/memory/Makefile.inc
@@ -6,4 +6,5 @@ OBJS += passes/memory/memory_collect.o
OBJS += passes/memory/memory_unpack.o
OBJS += passes/memory/memory_bram.o
OBJS += passes/memory/memory_map.o
+OBJS += passes/memory/memory_memx.o
diff --git a/passes/memory/memory.cc b/passes/memory/memory.cc
index e3c627607..947d598be 100644
--- a/passes/memory/memory.cc
+++ b/passes/memory/memory.cc
@@ -31,14 +31,15 @@ struct MemoryPass : public Pass {
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
- log(" memory [-nomap] [-nordff] [-bram <bram_rules>] [selection]\n");
+ log(" memory [-nomap] [-nordff] [-memx] [-bram <bram_rules>] [selection]\n");
log("\n");
log("This pass calls all the other memory_* passes in a useful order:\n");
log("\n");
- log(" memory_dff [-nordff]\n");
+ log(" memory_dff [-nordff] (-memx implies -nordff)\n");
log(" opt_clean\n");
log(" memory_share\n");
log(" opt_clean\n");
+ log(" memory_memx (when called with -memx)\n");
log(" memory_collect\n");
log(" memory_bram -rules <bram_rules> (when called with -bram)\n");
log(" memory_map (skipped if called with -nomap)\n");
@@ -51,6 +52,7 @@ struct MemoryPass : public Pass {
{
bool flag_nomap = false;
bool flag_nordff = false;
+ bool flag_memx = false;
string memory_bram_opts;
log_header(design, "Executing MEMORY pass.\n");
@@ -66,6 +68,11 @@ struct MemoryPass : public Pass {
flag_nordff = true;
continue;
}
+ if (args[argidx] == "-memx") {
+ flag_nordff = true;
+ flag_memx = true;
+ continue;
+ }
if (argidx+1 < args.size() && args[argidx] == "-bram") {
memory_bram_opts += " -rules " + args[++argidx];
continue;
@@ -77,6 +84,8 @@ struct MemoryPass : public Pass {
Pass::call(design, flag_nordff ? "memory_dff -nordff" : "memory_dff");
Pass::call(design, "opt_clean");
Pass::call(design, "memory_share");
+ if (flag_memx)
+ Pass::call(design, "memory_memx");
Pass::call(design, "opt_clean");
Pass::call(design, "memory_collect");
diff --git a/passes/memory/memory_memx.cc b/passes/memory/memory_memx.cc
new file mode 100644
index 000000000..2b02e2490
--- /dev/null
+++ b/passes/memory/memory_memx.cc
@@ -0,0 +1,92 @@
+/*
+ * yosys -- Yosys Open SYnthesis Suite
+ *
+ * Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/register.h"
+#include "kernel/log.h"
+#include <sstream>
+#include <set>
+#include <stdlib.h>
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct MemoryMemxPass : public Pass {
+ MemoryMemxPass() : Pass("memory_memx", "emulate vlog sim behavior for mem ports") { }
+ virtual void help()
+ {
+ // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+ log("\n");
+ log(" memory_memx [selection]\n");
+ log("\n");
+ log("This pass adds additional circuitry that emulates the Verilog simulation\n");
+ log("behavior for out-of-bounds memory reads and writes.\n");
+ log("\n");
+ }
+ virtual void execute(std::vector<std::string> args, RTLIL::Design *design) {
+ log_header(design, "Executing MEMORY_MEMX pass (converting $mem cells to logic and flip-flops).\n");
+ extra_args(args, 1, design);
+
+ for (auto module : design->selected_modules())
+ {
+ vector<Cell*> mem_port_cells;
+
+ for (auto cell : module->selected_cells())
+ if (cell->type.in("$memrd", "$memwr"))
+ mem_port_cells.push_back(cell);
+
+ for (auto cell : mem_port_cells)
+ {
+ IdString memid = cell->getParam("\\MEMID").decode_string();
+ RTLIL::Memory *mem = module->memories.at(memid);
+
+ int lowest_addr = mem->start_offset;
+ int highest_addr = mem->start_offset + mem->size - 1;
+
+ SigSpec addr = cell->getPort("\\ADDR");
+ addr.extend_u0(32);
+
+ SigSpec addr_ok = module->Nex(NEW_ID, module->ReduceXor(NEW_ID, addr), module->ReduceXor(NEW_ID, {addr, State::S1}));
+ if (lowest_addr != 0)
+ addr_ok = module->LogicAnd(NEW_ID, addr_ok, module->Ge(NEW_ID, addr, lowest_addr));
+ addr_ok = module->LogicAnd(NEW_ID, addr_ok, module->Le(NEW_ID, addr, highest_addr));
+
+ if (cell->type == "$memrd")
+ {
+ if (cell->getParam("\\CLK_ENABLE").as_bool())
+ log_error("Cell %s.%s (%s) has an enabled clock. Clocked $memrd cells are not supported by memory_memx!\n",
+ log_id(module), log_id(cell), log_id(cell->type));
+
+ SigSpec rdata = cell->getPort("\\DATA");
+ Wire *raw_rdata = module->addWire(NEW_ID, GetSize(rdata));
+ module->addMux(NEW_ID, SigSpec(State::Sx, GetSize(rdata)), raw_rdata, addr_ok, rdata);
+ cell->setPort("\\DATA", raw_rdata);
+ }
+
+ if (cell->type == "$memwr")
+ {
+ SigSpec en = cell->getPort("\\EN");
+ en = module->And(NEW_ID, en, addr_ok.repeat(GetSize(en)));
+ cell->setPort("\\EN", en);
+ }
+ }
+ }
+ }
+} MemoryMemxPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/techlibs/common/prep.cc b/techlibs/common/prep.cc
index ac1d98fde..8accb7e28 100644
--- a/techlibs/common/prep.cc
+++ b/techlibs/common/prep.cc
@@ -53,6 +53,10 @@ struct PrepPass : public ScriptPass
log(" passed to 'proc'. uses verilog simulation behavior for verilog if/case\n");
log(" undef handling. this also prevents 'wreduce' from being run.\n");
log("\n");
+ log(" -memx\n");
+ log(" simulate verilog simulation behavior for out-of-bounds memory accesses\n");
+ log(" using the 'memory_memx' pass. This option implies -nordff.\n");
+ log("\n");
log(" -nordff\n");
log(" passed to 'memory_dff'. prohibits merging of FFs into memory read ports\n");
log("\n");
@@ -68,7 +72,7 @@ struct PrepPass : public ScriptPass
}
string top_module, fsm_opts, memory_opts;
- bool autotop, flatten, ifxmode;
+ bool autotop, flatten, ifxmode, memxmode;
virtual void clear_flags() YS_OVERRIDE
{
@@ -78,6 +82,7 @@ struct PrepPass : public ScriptPass
autotop = false;
flatten = false;
ifxmode = false;
+ memxmode = false;
}
virtual void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
@@ -114,6 +119,11 @@ struct PrepPass : public ScriptPass
ifxmode = true;
continue;
}
+ if (args[argidx] == "-memx") {
+ memxmode = true;
+ memory_opts += " -nordff";
+ continue;
+ }
if (args[argidx] == "-nordff") {
memory_opts += " -nordff";
continue;
@@ -153,7 +163,10 @@ struct PrepPass : public ScriptPass
if (check_label("coarse"))
{
- run(ifxmode ? "proc -ifx" : "proc");
+ if (help_mode)
+ run("proc [-ifx]");
+ else
+ run(ifxmode ? "proc -ifx" : "proc");
if (help_mode || flatten)
run("flatten", "(if -flatten)");
run("opt_expr -keepdc");
@@ -163,6 +176,8 @@ struct PrepPass : public ScriptPass
if (!ifxmode)
run("wreduce");
run("memory_dff" + (help_mode ? " [-nordff]" : memory_opts));
+ if (help_mode || memxmode)
+ run("memory_memx", "(if -memx)");
run("opt_clean");
run("memory_collect");
run("opt -keepdc -fast");
--
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