From a91892bba422bbe8de080a105a6fb4b44f96df1a Mon Sep 17 00:00:00 2001 From: whitequark Date: Wed, 2 Jan 2019 07:53:31 +0000 Subject: cmp2lut: new techmap pass. --- techlibs/common/Makefile.inc | 2 +- techlibs/common/cmp2lut.v | 105 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 106 insertions(+), 1 deletion(-) create mode 100644 techlibs/common/cmp2lut.v (limited to 'techlibs/common') diff --git a/techlibs/common/Makefile.inc b/techlibs/common/Makefile.inc index 70074f653..0e05620bc 100644 --- a/techlibs/common/Makefile.inc +++ b/techlibs/common/Makefile.inc @@ -26,5 +26,5 @@ $(eval $(call add_share_file,share,techlibs/common/pmux2mux.v)) $(eval $(call add_share_file,share,techlibs/common/adff2dff.v)) $(eval $(call add_share_file,share,techlibs/common/dff2ff.v)) $(eval $(call add_share_file,share,techlibs/common/gate2lut.v)) +$(eval $(call add_share_file,share,techlibs/common/cmp2lut.v)) $(eval $(call add_share_file,share,techlibs/common/cells.lib)) - diff --git a/techlibs/common/cmp2lut.v b/techlibs/common/cmp2lut.v new file mode 100644 index 000000000..8aa1eb957 --- /dev/null +++ b/techlibs/common/cmp2lut.v @@ -0,0 +1,105 @@ +// Certain arithmetic operations between a signal of width n and a constant can be directly mapped +// to a single k-LUT (where n <= k). This is preferable to normal alumacc techmapping process +// because for many targets, arithmetic techmapping creates hard logic (such as carry cells) which often +// cannot be optimized further. +// +// TODO: Currently, only comparisons with 1-bit output are mapped. Potentially, all arithmetic cells +// with n <= k inputs should be techmapped in this way, because this shortens the critical path +// from n to 1 by avoiding carry chains. + +(* techmap_celltype = "$eq $ne $lt $le $gt $ge" *) +module _90_lut_cmp_ (A, B, Y); + +parameter A_SIGNED = 0; +parameter B_SIGNED = 0; +parameter A_WIDTH = 0; +parameter B_WIDTH = 0; +parameter Y_WIDTH = 0; + +input [A_WIDTH-1:0] A; +input [B_WIDTH-1:0] B; +output [Y_WIDTH-1:0] Y; + +parameter _TECHMAP_CELLTYPE_ = ""; + +parameter _TECHMAP_CONSTMSK_A_ = 0; +parameter _TECHMAP_CONSTVAL_A_ = 0; +parameter _TECHMAP_CONSTMSK_B_ = 0; +parameter _TECHMAP_CONSTVAL_B_ = 0; + +function automatic integer gen_lut; + input integer width; + input integer operation; + input integer swap; + input integer sign; + input integer operand; + integer n, i_var, i_cst, lhs, rhs, o_bit; + begin + gen_lut = width'b0; + for (n = 0; n < (1 << width); n++) begin + if (sign) + i_var = n[width-1:0]; + else + i_var = n; + i_cst = operand; + if (swap) begin + lhs = i_cst; + rhs = i_var; + end else begin + lhs = i_var; + rhs = i_cst; + end + if (operation == 0) + o_bit = (lhs < rhs); + if (operation == 1) + o_bit = (lhs <= rhs); + if (operation == 2) + o_bit = (lhs > rhs); + if (operation == 3) + o_bit = (lhs >= rhs); + if (operation == 4) + o_bit = (lhs == rhs); + if (operation == 5) + o_bit = (lhs != rhs); + gen_lut = gen_lut | (o_bit << n); + end + end +endfunction + +generate + if (_TECHMAP_CELLTYPE_ == "$lt") + localparam operation = 0; + if (_TECHMAP_CELLTYPE_ == "$le") + localparam operation = 1; + if (_TECHMAP_CELLTYPE_ == "$gt") + localparam operation = 2; + if (_TECHMAP_CELLTYPE_ == "$ge") + localparam operation = 3; + if (_TECHMAP_CELLTYPE_ == "$eq") + localparam operation = 4; + if (_TECHMAP_CELLTYPE_ == "$ne") + localparam operation = 5; + + if (A_WIDTH > `LUT_WIDTH || B_WIDTH > `LUT_WIDTH || Y_WIDTH != 1) + wire _TECHMAP_FAIL_ = 1; + else if (&_TECHMAP_CONSTMSK_B_) + \$lut #( + .WIDTH(A_WIDTH), + .LUT({ gen_lut(A_WIDTH, operation, 0, A_SIGNED && B_SIGNED, _TECHMAP_CONSTVAL_B_) }) + ) _TECHMAP_REPLACE_ ( + .A(A), + .Y(Y) + ); + else if (&_TECHMAP_CONSTMSK_A_) + \$lut #( + .WIDTH(B_WIDTH), + .LUT({ gen_lut(B_WIDTH, operation, 1, A_SIGNED && B_SIGNED, _TECHMAP_CONSTVAL_A_) }) + ) _TECHMAP_REPLACE_ ( + .A(B), + .Y(Y) + ); + else + wire _TECHMAP_FAIL_ = 1; +endgenerate + +endmodule -- cgit v1.2.3 From fdff32dd731d92c854aef73ea9fad89635e82c0f Mon Sep 17 00:00:00 2001 From: whitequark Date: Wed, 2 Jan 2019 08:05:44 +0000 Subject: synth: improve script documentation. NFC. --- techlibs/common/synth.cc | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'techlibs/common') diff --git a/techlibs/common/synth.cc b/techlibs/common/synth.cc index efb214759..5cadbba7a 100644 --- a/techlibs/common/synth.cc +++ b/techlibs/common/synth.cc @@ -186,19 +186,19 @@ struct SynthPass : public ScriptPass { run("proc"); if (help_mode || flatten) - run("flatten", "(if -flatten)"); + run("flatten", " (if -flatten)"); run("opt_expr"); run("opt_clean"); run("check"); run("opt"); run("wreduce"); if (!noalumacc) - run("alumacc"); + run("alumacc", " (unless -noalumacc)"); if (!noshare) - run("share"); + run("share", " (unless -noshare)"); run("opt"); if (!nofsm) - run("fsm" + fsm_opts); + run("fsm" + fsm_opts, " (unless -nofsm)"); run("opt -fast"); run("memory -nomap" + memory_opts); run("opt_clean"); @@ -214,8 +214,8 @@ struct SynthPass : public ScriptPass if (!noabc) { #ifdef YOSYS_ENABLE_ABC - run("abc -fast"); - run("opt -fast"); + run("abc -fast", "(unless -noabc)"); + run("opt -fast", "(unless -noabc)"); #endif } } -- cgit v1.2.3 From 18174202a957cb20137e13893ad002ac1b52b61b Mon Sep 17 00:00:00 2001 From: whitequark Date: Wed, 2 Jan 2019 08:25:03 +0000 Subject: synth: add k-LUT mode. --- techlibs/common/synth.cc | 38 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-) (limited to 'techlibs/common') diff --git a/techlibs/common/synth.cc b/techlibs/common/synth.cc index 5cadbba7a..5ff813d18 100644 --- a/techlibs/common/synth.cc +++ b/techlibs/common/synth.cc @@ -51,6 +51,9 @@ struct SynthPass : public ScriptPass log(" -encfile \n"); log(" passed to 'fsm_recode' via 'fsm'\n"); log("\n"); + log(" -lut \n"); + log(" perform synthesis for a k-LUT architecture.\n"); + log("\n"); log(" -nofsm\n"); log(" do not run FSM optimization\n"); log("\n"); @@ -80,6 +83,7 @@ struct SynthPass : public ScriptPass string top_module, fsm_opts, memory_opts; bool autotop, flatten, noalumacc, nofsm, noabc, noshare; + int lut; void clear_flags() YS_OVERRIDE { @@ -89,6 +93,7 @@ struct SynthPass : public ScriptPass autotop = false; flatten = false; + lut = 0; noalumacc = false; nofsm = false; noabc = false; @@ -130,6 +135,10 @@ struct SynthPass : public ScriptPass flatten = true; continue; } + if (args[argidx] == "-lut") { + lut = atoi(args[++argidx].c_str()); + continue; + } if (args[argidx] == "-nofsm") { nofsm = true; continue; @@ -192,6 +201,10 @@ struct SynthPass : public ScriptPass run("check"); run("opt"); run("wreduce"); + if (help_mode) + run("techmap -map +/cmp2lut.v", " (if -lut)"); + else + run(stringf("techmap -map +/cmp2lut.v -D LUT_WIDTH=%d", lut)); if (!noalumacc) run("alumacc", " (unless -noalumacc)"); if (!noshare) @@ -210,12 +223,33 @@ struct SynthPass : public ScriptPass run("memory_map"); run("opt -full"); run("techmap"); + if (help_mode) + { + run("techmap -map +/gate2lut.v", "(if -noabc and -lut)"); + run("clean; opt_lut", " (if -noabc and -lut)"); + } + else if (noabc && lut) + { + run(stringf("techmap -map +/gate2lut.v -D LUT_WIDTH=%d", lut)); + run("clean; opt_lut"); + } run("opt -fast"); if (!noabc) { #ifdef YOSYS_ENABLE_ABC - run("abc -fast", "(unless -noabc)"); - run("opt -fast", "(unless -noabc)"); + if (help_mode) + { + run("abc -fast", " (unless -noabc, unless -lut)"); + run("abc -fast -lut k", "(unless -noabc, if -lut)"); + } + else + { + if (lut) + run(stringf("abc -fast -lut %d", lut)); + else + run("abc -fast"); + } + run("opt -fast", " (unless -noabc)"); #endif } } -- cgit v1.2.3 From efa278e232d20ea080743801bd91d55ec62955cf Mon Sep 17 00:00:00 2001 From: whitequark Date: Fri, 7 Dec 2018 19:14:07 +0000 Subject: Fix typographical and grammatical errors and inconsistencies. The initial list of hits was generated with the codespell command below, and each hit was evaluated and fixed manually while taking context into consideration. DIRS="kernel/ frontends/ backends/ passes/ techlibs/" DIRS="${DIRS} libs/ezsat/ libs/subcircuit" codespell $DIRS -S *.o -L upto,iff,thru,synopsys,uint More hits were found by looking through comments and strings manually. --- techlibs/common/prep.cc | 2 +- techlibs/common/synth.cc | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'techlibs/common') diff --git a/techlibs/common/prep.cc b/techlibs/common/prep.cc index 897f37dbb..86fb4d6c6 100644 --- a/techlibs/common/prep.cc +++ b/techlibs/common/prep.cc @@ -153,7 +153,7 @@ struct PrepPass : public ScriptPass extra_args(args, argidx, design); if (!design->full_selection()) - log_cmd_error("This comannd only operates on fully selected designs!\n"); + log_cmd_error("This command only operates on fully selected designs!\n"); log_header(design, "Executing PREP pass.\n"); log_push(); diff --git a/techlibs/common/synth.cc b/techlibs/common/synth.cc index efb214759..d9565131e 100644 --- a/techlibs/common/synth.cc +++ b/techlibs/common/synth.cc @@ -155,7 +155,7 @@ struct SynthPass : public ScriptPass extra_args(args, argidx, design); if (!design->full_selection()) - log_cmd_error("This comannd only operates on fully selected designs!\n"); + log_cmd_error("This command only operates on fully selected designs!\n"); log_header(design, "Executing SYNTH pass.\n"); log_push(); -- cgit v1.2.3