From 7d014902ec579eccd04446131fea4772dd715daf Mon Sep 17 00:00:00 2001 From: Henner Zeller Date: Thu, 21 Jan 2021 12:20:53 -0800 Subject: [PATCH] Fix digit-formatting calculation for small numbers. Calling log10() on zero causes a non-sensical value to be calculated. On some compile options, I've observed yosys crashing with an illegal instruction (SIGILL). To make it safe, fix the calculation to do a range check; wrap it a decimal_digits() function, and use it where the previous ceil(log10(n)) call was used. As a side, it also improves readability. Signed-off-by: Henner Zeller --- frontends/aiger/aigerparse.cc | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/frontends/aiger/aigerparse.cc b/frontends/aiger/aigerparse.cc index 07e3cd6e0..2d7c2187e 100644 --- a/frontends/aiger/aigerparse.cc +++ b/frontends/aiger/aigerparse.cc @@ -55,6 +55,10 @@ inline int32_t from_big_endian(int32_t i32) { #define log_debug2(...) ; //#define log_debug2(...) log_debug(__VA_ARGS__) +static int decimal_digits(unsigned n) { + return n > 1 ? ceil(log10(n)) : 1; +} + struct ConstEvalAig { RTLIL::Module *module; @@ -515,7 +519,7 @@ void AigerReader::parse_aiger_ascii() unsigned l1, l2, l3; // Parse inputs - int digits = ceil(log10(I)); + int digits = decimal_digits(I); for (unsigned i = 1; i <= I; ++i, ++line_count) { if (!(f >> l1)) log_error("Line %u cannot be interpreted as an input!\n", line_count); @@ -537,7 +541,7 @@ void AigerReader::parse_aiger_ascii() clk_wire->port_input = true; clk_wire->port_output = false; } - digits = ceil(log10(L)); + digits = decimal_digits(L); for (unsigned i = 0; i < L; ++i, ++line_count) { if (!(f >> l1 >> l2)) log_error("Line %u cannot be interpreted as a latch!\n", line_count); @@ -575,7 +579,7 @@ void AigerReader::parse_aiger_ascii() } // Parse outputs - digits = ceil(log10(O)); + digits = decimal_digits(O); for (unsigned i = 0; i < O; ++i, ++line_count) { if (!(f >> l1)) log_error("Line %u cannot be interpreted as an output!\n", line_count); @@ -643,7 +647,7 @@ void AigerReader::parse_aiger_binary() std::string line; // Parse inputs - int digits = ceil(log10(I)); + int digits = decimal_digits(I); for (unsigned i = 1; i <= I; ++i) { log_debug2("%d is an input\n", i); RTLIL::Wire *wire = module->addWire(stringf("$i%0*d", digits, i)); @@ -662,7 +666,7 @@ void AigerReader::parse_aiger_binary() clk_wire->port_input = true; clk_wire->port_output = false; } - digits = ceil(log10(L)); + digits = decimal_digits(L); l1 = (I+1) * 2; for (unsigned i = 0; i < L; ++i, ++line_count, l1 += 2) { if (!(f >> l2)) @@ -700,7 +704,7 @@ void AigerReader::parse_aiger_binary() } // Parse outputs - digits = ceil(log10(O)); + digits = decimal_digits(O); for (unsigned i = 0; i < O; ++i, ++line_count) { if (!(f >> l1)) log_error("Line %u cannot be interpreted as an output!\n", line_count); -- 2.30.2