The vvp `%load/vec4a` instruction will skip the load if vvp flag 4 is set and return 'x. This is meant for handling the case where the index is undefined. For assignment operators on array entries, when the index is an immediate value, vvp flag 4 is not cleared before the load instruction. If a previous instruction set flag 4 it load yield 'x. E.g. for the following sequence `x[0]` should be `11`, but will be `'x`. ``` integer x[10]; logic a = 1'b0; x[0] = 10; if (a == 0) begin x[0] += 1; end ``` Properly clear the flag before the load instruction to handle this correctly. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> |
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| .. | ||
| COPYING.lesser | ||
| Makefile.in | ||
| README.txt | ||
| cppcheck.sup | ||
| draw_class.c | ||
| draw_delay.c | ||
| draw_enum.c | ||
| draw_mux.c | ||
| draw_net_input.c | ||
| draw_substitute.c | ||
| draw_switch.c | ||
| draw_ufunc.c | ||
| draw_vpi.c | ||
| eval_condit.c | ||
| eval_expr.c | ||
| eval_object.c | ||
| eval_real.c | ||
| eval_string.c | ||
| eval_vec4.c | ||
| modpath.c | ||
| stmt_assign.c | ||
| vvp-s.conf.in | ||
| vvp.c | ||
| vvp.conf.in | ||
| vvp_config.h.in | ||
| vvp_priv.h | ||
| vvp_process.c | ||
| vvp_scope.c | ||
README.txt
THE VVP TARGET SYMBOL NAME CONVENTIONS There are some naming conventions that the vvp target uses for generating symbol names. * wires and regs Nets and variables are named V_<full-name> where <full-name> is the full hierarchical name of the signal. * Logic devices Logic devices (and, or, buf, bufz, etc.) are named L_<full_name>. In this case the symbol is attached to a functor that is the output of the logic device. GENERAL FUNCTOR WEB STRUCTURE The net of gates, signals and resolvers is formed from the input design. The basic structure is wrapped around the nexus, which is represented by the ivl_nexus_t. Each nexus represents a resolved value. The input of the nexus is fed by a single driver. If the nexus in the design has multiple drivers, the drivers are first fed into a resolver (or a tree of resolvers) to form a single output that is the nexus. The nexus, then, feeds its output to the inputs of other gates, or to the .net objects in the design.