From 22c967e35e23d0688081818f49a11f0ec0853bb1 Mon Sep 17 00:00:00 2001 From: David Shah Date: Sun, 19 Jan 2020 21:15:51 +0000 Subject: [PATCH] ast: Add support for $sformatf system function Signed-off-by: David Shah --- frontends/ast/ast.h | 1 + frontends/ast/simplify.cc | 202 ++++++++++++++++++++------------------ tests/various/sformatf.ys | 12 +++ 3 files changed, 122 insertions(+), 93 deletions(-) create mode 100644 tests/various/sformatf.ys diff --git a/frontends/ast/ast.h b/frontends/ast/ast.h index 918d178c7..14e1cec5e 100644 --- a/frontends/ast/ast.h +++ b/frontends/ast/ast.h @@ -244,6 +244,7 @@ namespace AST void replace_variables(std::map &variables, AstNode *fcall); AstNode *eval_const_function(AstNode *fcall); bool is_simple_const_expr(); + std::string process_format_str(const std::string &sformat, int next_arg, int stage, int width_hint, bool sign_hint); // create a human-readable text representation of the AST (for debugging) void dumpAst(FILE *f, std::string indent) const; diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc index b94a8d710..8855d9954 100644 --- a/frontends/ast/simplify.cc +++ b/frontends/ast/simplify.cc @@ -41,6 +41,103 @@ YOSYS_NAMESPACE_BEGIN using namespace AST; using namespace AST_INTERNAL; +// Process a format string and arguments for $display, $write, $sprintf, etc + +std::string AstNode::process_format_str(const std::string &sformat, int next_arg, int stage, int width_hint, bool sign_hint) { + // Other arguments are placeholders. Process the string as we go through it + std::string sout; + for (size_t i = 0; i < sformat.length(); i++) + { + // format specifier + if (sformat[i] == '%') + { + // If there's no next character, that's a problem + if (i+1 >= sformat.length()) + log_file_error(filename, linenum, "System task `%s' called with `%%' at end of string.\n", str.c_str()); + + char cformat = sformat[++i]; + + // %% is special, does not need a matching argument + if (cformat == '%') + { + sout += '%'; + continue; + } + + // Simplify the argument + AstNode *node_arg = nullptr; + + // Everything from here on depends on the format specifier + switch (cformat) + { + case 's': + case 'S': + case 'd': + case 'D': + case 'x': + case 'X': + if (next_arg >= GetSize(children)) + log_file_error(filename, linenum, "Missing argument for %%%c format specifier in system task `%s'.\n", + cformat, str.c_str()); + + node_arg = children[next_arg++]; + while (node_arg->simplify(true, false, false, stage, width_hint, sign_hint, false)) { } + if (node_arg->type != AST_CONSTANT) + log_file_error(filename, linenum, "Failed to evaluate system task `%s' with non-constant argument.\n", str.c_str()); + break; + + case 'm': + case 'M': + break; + + default: + log_file_error(filename, linenum, "System task `%s' called with invalid/unsupported format specifier.\n", str.c_str()); + break; + } + + switch (cformat) + { + case 's': + case 'S': + sout += node_arg->bitsAsConst().decode_string(); + break; + + case 'd': + case 'D': + { + char tmp[128]; + snprintf(tmp, sizeof(tmp), "%d", node_arg->bitsAsConst().as_int()); + sout += tmp; + } + break; + + case 'x': + case 'X': + { + char tmp[128]; + snprintf(tmp, sizeof(tmp), "%x", node_arg->bitsAsConst().as_int()); + sout += tmp; + } + break; + + case 'm': + case 'M': + sout += log_id(current_module->name); + break; + + default: + log_abort(); + } + } + + // not a format specifier + else + sout += sformat[i]; + } + return sout; +} + + // convert the AST into a simpler AST that has all parameters substituted by their // values, unrolled for-loops, expanded generate blocks, etc. when this function // is done with an AST it can be converted into RTLIL using genRTLIL(). @@ -216,99 +313,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage, if (node_string->type != AST_CONSTANT) log_file_error(filename, linenum, "Failed to evaluate system task `%s' with non-constant 1st argument.\n", str.c_str()); std::string sformat = node_string->bitsAsConst().decode_string(); - - // Other arguments are placeholders. Process the string as we go through it - std::string sout; - int next_arg = 1; - for (size_t i = 0; i < sformat.length(); i++) - { - // format specifier - if (sformat[i] == '%') - { - // If there's no next character, that's a problem - if (i+1 >= sformat.length()) - log_file_error(filename, linenum, "System task `%s' called with `%%' at end of string.\n", str.c_str()); - - char cformat = sformat[++i]; - - // %% is special, does not need a matching argument - if (cformat == '%') - { - sout += '%'; - continue; - } - - // Simplify the argument - AstNode *node_arg = nullptr; - - // Everything from here on depends on the format specifier - switch (cformat) - { - case 's': - case 'S': - case 'd': - case 'D': - case 'x': - case 'X': - if (next_arg >= GetSize(children)) - log_file_error(filename, linenum, "Missing argument for %%%c format specifier in system task `%s'.\n", - cformat, str.c_str()); - - node_arg = children[next_arg++]; - while (node_arg->simplify(true, false, false, stage, width_hint, sign_hint, false)) { } - if (node_arg->type != AST_CONSTANT) - log_file_error(filename, linenum, "Failed to evaluate system task `%s' with non-constant argument.\n", str.c_str()); - break; - - case 'm': - case 'M': - break; - - default: - log_file_error(filename, linenum, "System task `%s' called with invalid/unsupported format specifier.\n", str.c_str()); - break; - } - - switch (cformat) - { - case 's': - case 'S': - sout += node_arg->bitsAsConst().decode_string(); - break; - - case 'd': - case 'D': - { - char tmp[128]; - snprintf(tmp, sizeof(tmp), "%d", node_arg->bitsAsConst().as_int()); - sout += tmp; - } - break; - - case 'x': - case 'X': - { - char tmp[128]; - snprintf(tmp, sizeof(tmp), "%x", node_arg->bitsAsConst().as_int()); - sout += tmp; - } - break; - - case 'm': - case 'M': - sout += log_id(current_module->name); - break; - - default: - log_abort(); - } - } - - // not a format specifier - else - sout += sformat[i]; - } - + std::string sout = process_format_str(sformat, 1, stage, width_hint, sign_hint); // Finally, print the message (only include a \n for $display, not for $write) log("%s", sout.c_str()); if (str == "$display") @@ -2244,6 +2249,17 @@ skip_dynamic_range_lvalue_expansion:; goto apply_newNode; } + if (str == "\\$sformatf") { + AstNode *node_string = children[0]; + while (node_string->simplify(true, false, false, stage, width_hint, sign_hint, false)) { } + if (node_string->type != AST_CONSTANT) + log_file_error(filename, linenum, "Failed to evaluate system function `%s' with non-constant 1st argument.\n", str.c_str()); + std::string sformat = node_string->bitsAsConst().decode_string(); + std::string sout = process_format_str(sformat, 1, stage, width_hint, sign_hint); + newNode = AstNode::mkconst_str(sout); + goto apply_newNode; + } + if (current_scope.count(str) != 0 && current_scope[str]->type == AST_DPI_FUNCTION) { AstNode *dpi_decl = current_scope[str]; diff --git a/tests/various/sformatf.ys b/tests/various/sformatf.ys new file mode 100644 index 000000000..66d6b0dbe --- /dev/null +++ b/tests/various/sformatf.ys @@ -0,0 +1,12 @@ +read_verilog <