diff options
| author | Andy Walls <awalls.cx18@gmail.com> | 2018-01-05 15:48:26 -0500 |
|---|---|---|
| committer | Marcus Müller <marcus@hostalia.de> | 2018-08-23 19:31:13 +0200 |
| commit | b09536999ebf45065fd4b06dd40a56782991b492 (patch) | |
| tree | fa1c8dfb1829c72f871e039b66d2e0f7679b8137 /gnuradio-runtime/lib/block_executor.cc | |
| parent | 9ea30c8d94f006649ec4626cbc333e93e5c029a5 (diff) | |
runtime: Use multiprecision rational arithmetic to propagate tags
Avoid floating point precision problems in propagation of tags for
the following cases:
- Common relative rates that are non-terminating in binary (1/3, 1/5, 1/7, ...)
- Large tag offsets
- Inexact floating point reciprocals when specifying the relative rate
This change to the runtime only fixes the tag propagation problems for
blocks with a fixed/unchanging relative rate.
This change adds a dependency on the MIPR library (a fork of the GMP
library) to perform multiple precision interger rational arithmetic.
MIPR was chosen as it purports to maintain a properly working Windows
build for cross-platform compatability. Optimizations in MIPR are
also targeted to ARM in additional to x86-64.
Diffstat (limited to 'gnuradio-runtime/lib/block_executor.cc')
| -rw-r--r-- | gnuradio-runtime/lib/block_executor.cc | 54 |
1 files changed, 41 insertions, 13 deletions
diff --git a/gnuradio-runtime/lib/block_executor.cc b/gnuradio-runtime/lib/block_executor.cc index 754744449a..6152ff6765 100644 --- a/gnuradio-runtime/lib/block_executor.cc +++ b/gnuradio-runtime/lib/block_executor.cc @@ -94,8 +94,11 @@ namespace gr { static bool propagate_tags(block::tag_propagation_policy_t policy, block_detail *d, const std::vector<uint64_t> &start_nitems_read, double rrate, + mpq_class &mp_rrate, bool use_fp_rrate, std::vector<tag_t> &rtags, long block_id) { + static const mpq_class one_half(1, 2); + // Move tags downstream // if a sink, we don't need to move downstream if(d->sink_p()) { @@ -131,7 +134,7 @@ namespace gr { out_buf[o]->add_item_tag(*t); } } - else { + else if(use_fp_rrate) { for(t = rtags.begin(); t != rtags.end(); t++) { tag_t new_tag = *t; new_tag.offset = ((double)new_tag.offset * rrate) + 0.5; @@ -139,6 +142,16 @@ namespace gr { out_buf[o]->add_item_tag(new_tag); } } + else { + mpz_class offset; + for(t = rtags.begin(); t != rtags.end(); t++) { + tag_t new_tag = *t; + offset = new_tag.offset * mp_rrate + one_half; + new_tag.offset = offset.get_ui(); + for(int o = 0; o < d->noutputs(); o++) + out_buf[o]->add_item_tag(new_tag); + } + } } } break; @@ -159,10 +172,26 @@ namespace gr { out_buf = d->output(i); std::vector<tag_t>::iterator t; - for(t = rtags.begin(); t != rtags.end(); t++) { - tag_t new_tag = *t; - new_tag.offset = ((double)new_tag.offset * rrate) + 0.5; - out_buf->add_item_tag(new_tag); + if(rrate == 1.0) { + for(t = rtags.begin(); t != rtags.end(); t++) { + out_buf->add_item_tag(*t); + } + } + else if(use_fp_rrate) { + for(t = rtags.begin(); t != rtags.end(); t++) { + tag_t new_tag = *t; + new_tag.offset = ((double)new_tag.offset * rrate) + 0.5; + out_buf->add_item_tag(new_tag); + } + } + else { + mpz_class offset; + for(t = rtags.begin(); t != rtags.end(); t++) { + tag_t new_tag = *t; + offset = new_tag.offset * mp_rrate + one_half; + new_tag.offset = offset.get_ui(); + out_buf->add_item_tag(new_tag); + } } } } @@ -212,7 +241,6 @@ namespace gr { int max_noutput_items; int new_alignment = 0; int alignment_state = -1; - double rrate; block *m = d_block.get(); block_detail *d = m->detail().get(); @@ -321,10 +349,8 @@ namespace gr { noutput_items = min_available_space(d, m->output_multiple(), m->min_noutput_items()); if(ENABLE_LOGGING) { *d_log << " regular "; - if(m->relative_rate() >= 1.0) - *d_log << "1:" << m->relative_rate() << std::endl; - else - *d_log << 1.0/m->relative_rate() << ":1\n"; + *d_log << m->relative_rate_i() << ":" + << m->relative_rate_d() << std::endl; *d_log << " max_items_avail = " << max_items_avail << std::endl; *d_log << " noutput_items = " << noutput_items << std::endl; } @@ -490,6 +516,7 @@ namespace gr { // Now propagate the tags based on the new relative rate if(!propagate_tags(m->tag_propagation_policy(), d, d_start_nitems_read, m->relative_rate(), + m->mp_relative_rate(), m->update_rate(), d_returned_tags, m->unique_id())) goto were_done; @@ -505,9 +532,10 @@ namespace gr { // In the block constructor, use enable_update_rate(true). if(m->update_rate()) { //rrate = ((double)(m->nitems_written(0))) / ((double)m->nitems_read(0)); - rrate = (double)n / (double)d->consumed(); - if(rrate > 0) - m->set_relative_rate(rrate); + //if(rrate > 0.0) + // m->set_relative_rate(rrate); + if((n > 0) && (d->consumed() > 0)) + m->set_relative_rate((uint64_t)n, (uint64_t)d->consumed()); } if(d->d_produce_or > 0) // block produced something |