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Fix tinyram prelude, tinyram read from aux input. #90

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Fix tinyram prelude, tinyram read from aux input. #90

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6 changes: 3 additions & 3 deletions libsnark/gadgetlib1/gadgets/cpu_checkers/tinyram/tinyram_cpu_checker.tcc
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Original file line number Diff line number Diff line change
Expand Up @@ -326,12 +326,12 @@ void tinyram_cpu_checker<FieldT>::generate_r1cs_witness_other(tinyram_input_tape
}

this->pb.val(read_not1) = this->pb.val(opcode_indicators[tinyram_opcode_READ]) * (FieldT::one() - this->pb.val(arg2val->packed));
if (this->pb.val(read_not1) != FieldT::one())
if (this->pb.val(read_not1) != FieldT::zero())
{
/* reading from tape other than 0 raises the flag */
/* reading from tape other than 1 raises the flag */
this->pb.val(instruction_flags[tinyram_opcode_READ]) = FieldT::one();
}
else
else if (this->pb.val(opcode_indicators[tinyram_opcode_READ]) != FieldT::zero())
{
/* otherwise perform the actual read */
if (aux_it != aux_end)
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2 changes: 1 addition & 1 deletion libsnark/relations/ram_computations/rams/tinyram/tinyram_aux.cpp
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Expand Up @@ -117,7 +117,7 @@ void ensure_tinyram_opcode_value_map()
std::vector<tinyram_instruction> generate_tinyram_prelude(const tinyram_architecture_params &ap)
{
std::vector<tinyram_instruction> result;
const size_t increment = libff::log2(ap.w)/8;
const size_t increment = ap.w/8;
const size_t mem_start = 1ul<<(ap.w-1);
result.emplace_back(tinyram_instruction(tinyram_opcode_STOREW, true, 0, 0, 0)); // 0: store.w 0, r0
result.emplace_back(tinyram_instruction(tinyram_opcode_MOV, true, 0, 0, mem_start)); // 1: mov r0, 2^{W-1}
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