$past now supports array and struct types
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tautschnig
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Aug 28, 2025
src/verilog/verilog_expr.cpp
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| exprt verilog_past_exprt::default_value(const typet &type) | ||
| { | ||
| auto zero = from_integer(0, type()); | ||
| if(zero.is_nil()) | ||
| throw "failed to create $past default value"; | ||
| if(type.id() == ID_array) | ||
| { | ||
| auto &array_type = to_array_type(type); | ||
| auto zero_rec = default_value(array_type.element_type()); | ||
| return array_of_exprt{zero_rec, array_type}; | ||
| } | ||
| else | ||
| return std::move(zero); | ||
| { | ||
| return from_integer(0, type); | ||
| } | ||
| } |
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Shouldn't this use CBMC's zero_initializer or else the one for Verilog being proposed in #1001?
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Yes, the standard seems to guarantee that the value prior to the initial state is the default initial value, will consolidate.
kroening
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This merges the types in struct and union declarations.
$past returns a "zero value" when asked for a value prior to the initial frame. This adds the zero value for array and struct types.
kroening
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$past now supports array types$past now supports array and struct types
tautschnig
approved these changes
Aug 30, 2025
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$pastreturns a "zero value" when asked for a value prior to the initial frame. This adds the zero value for array and struct types.