riscv
/
yosys
mirror of https://github.com/YosysHQ/yosys.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Add support for overflow using pattern detector

This commit is contained in:
Eddie Hung 2019-09-18 09:39:59 -07:00
parent 0932e23dff
commit 1f18736d20
2 changed files with 31 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
passes/pmgen/xilinx_dsp.cc
View File

@ -271,6 +271,7 @@ void pack_xilinx_dsp(dict<SigBit, Cell*> &bit_to_driver, xilinx_dsp_pm &pm)
log("postAdd: %s\n", log_id(st.postAdd, "--"));
log("postAddMux: %s\n", log_id(st.postAddMux, "--"));
log("ffP: %s %s %s\n", log_id(st.ffP, "--"), log_id(st.ffPcemux, "--"), log_id(st.ffPrstmux, "--"));
log("overflow: %s\n", log_id(st.overflow, "--"));
#endif
log("Analysing %s.%s for Xilinx DSP packing.\n", log_id(pm.module), log_id(st.dsp));
@ -329,6 +330,24 @@ void pack_xilinx_dsp(dict<SigBit, Cell*> &bit_to_driver, xilinx_dsp_pm &pm)
pm.autoremove(st.postAdd);
}
if (st.overflow) {
log(" overflow %s (%s)\n", log_id(st.overflow), log_id(st.overflow->type));
cell->setParam("\\USE_PATTERN_DETECT", Const("PATDET"));
cell->setParam("\\SEL_PATTERN", Const("PATTERN"));
cell->setParam("\\SEL_MASK", Const("MASK"));
if (st.overflow->type == "$ge") {
int B = st.overflow->getPort("\\B").as_int();
log_assert((B & (B-1)) == 0); // Exact power of 2
cell->setParam("\\MASK", Const(B-1, 48));
cell->setParam("\\PATTERN", Const(0, 48));
cell->setPort("\\OVERFLOW", st.overflow->getPort("\\Y"));
}
else log_abort();
pm.autoremove(st.overflow);
}
if (st.clock != SigBit())
{

13
passes/pmgen/xilinx_dsp.pmg
View File

@ -264,7 +264,6 @@ match postAdd
select postAdd->type.in($add)
select GetSize(port(postAdd, \Y)) <= 48
select nusers(port(postAdd, \Y)) == 2
choice <IdString> AB {\A, \B}
select nusers(port(postAdd, AB)) <= 3
filter ffMcemux || nusers(port(postAdd, AB)) == 2
@ -356,6 +355,18 @@ code argQ ffC ffCcemux ffCrstmux ffCcepol ffCrstpol sigC clock
}
endcode
match overflow
if ffP
if dsp->parameters.at(\USE_PATTERN_DETECT, Const("NO_PATDET")).decode_string() == "NO_PATDET"
select overflow->type.in($ge)
select GetSize(port(overflow, \Y)) <= 48
select port(overflow, \B).is_fully_const()
// Check is exact power of 2
select (port(overflow, \B).as_int() & (port(overflow, \B).as_int()-1)) == 0
index <SigSpec> port(overflow, \A) === sigP
optional
endmatch
code
accept;
endcode