From 0b223f4001fce26cad3b3c7e03501e7222d85ee0 Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Wed, 5 Apr 2017 16:38:00 +0100 Subject: power: Add error checking to MathExprPowerModel MathExprPower model currently doesn't print any useful error messages if an expression fails to evaluate. To add insult to injury, the model only detects a failure when dumping stats and not at initialization. This change adds a verification step in startup() that ensures that all of the referenced stats actually exist. Change-Id: I8f71c73341578d5882c8d93e482f5383fbda5f1d Signed-off-by: Andreas Sandberg Reviewed-by: Nikos Nikoleris Reviewed-by: Sascha Bischoff Reviewed-on: https://gem5-review.googlesource.com/2661 Reviewed-by: Jason Lowe-Power Maintainer: Jason Lowe-Power --- src/sim/power/mathexpr_powermodel.cc | 59 +++++++++++++++++++++++++++++++++--- src/sim/power/mathexpr_powermodel.hh | 37 ++++++++++++++-------- 2 files changed, 78 insertions(+), 18 deletions(-) (limited to 'src/sim') diff --git a/src/sim/power/mathexpr_powermodel.cc b/src/sim/power/mathexpr_powermodel.cc index 7bd218659..13d225ee3 100644 --- a/src/sim/power/mathexpr_powermodel.cc +++ b/src/sim/power/mathexpr_powermodel.cc @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016 ARM Limited + * Copyright (c) 2016-2017 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -46,7 +46,7 @@ #include "sim/sim_object.hh" MathExprPowerModel::MathExprPowerModel(const Params *p) - : PowerModelState(p), dyn_expr(p->dyn), st_expr(p->st) + : PowerModelState(p), dyn_expr(p->dyn), st_expr(p->st), failed(false) { // Calculate the name of the object we belong to std::vector path; @@ -65,8 +65,50 @@ MathExprPowerModel::startup() for (auto & i: Stats::statsList()) if (i->name.find(basename) == 0) stats_map[i->name.substr(basename.size())] = i; + + tryEval(st_expr); + const bool st_failed = failed; + + tryEval(dyn_expr); + const bool dyn_failed = failed; + + if (st_failed || dyn_failed) { + const auto *p = dynamic_cast(params()); + assert(p); + + fatal("Failed to evaluate power expressions:\n%s%s%s\n", + st_failed ? p->st : "", + st_failed && dyn_failed ? "\n" : "", + dyn_failed ? p->dyn : ""); + } } +double +MathExprPowerModel::eval(const MathExpr &expr) const +{ + const double value = tryEval(expr); + + // This shouldn't happen unless something went wrong the equations + // were verified in startup(). + panic_if(failed, "Failed to evaluate power expression '%s'\n", + expr.toStr()); + + return value; +} + +double +MathExprPowerModel::tryEval(const MathExpr &expr) const +{ + failed = false; + const double value = expr.eval( + std::bind(&MathExprPowerModel::getStatValue, + this, std::placeholders::_1) + ); + + return value; +} + + double MathExprPowerModel::getStatValue(const std::string &name) const { @@ -77,12 +119,19 @@ MathExprPowerModel::getStatValue(const std::string &name) const return _temp; // Try to cast the stat, only these are supported right now - Info *info = stats_map.at(name); + const auto it = stats_map.find(name); + if (it == stats_map.cend()) { + warn("Failed to find stat '%s'\n", name); + failed = true; + return 0; + } + + const Info *info = it->second; - ScalarInfo *si = dynamic_cast(info); + auto si = dynamic_cast(info); if (si) return si->value(); - FormulaInfo *fi = dynamic_cast(info); + auto fi = dynamic_cast(info); if (fi) return fi->total(); diff --git a/src/sim/power/mathexpr_powermodel.hh b/src/sim/power/mathexpr_powermodel.hh index 5c121c7b6..b4d0254d8 100644 --- a/src/sim/power/mathexpr_powermodel.hh +++ b/src/sim/power/mathexpr_powermodel.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016 ARM Limited + * Copyright (c) 2016-2017 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -66,24 +66,14 @@ class MathExprPowerModel : public PowerModelState * * @return Power (Watts) consumed by this object (dynamic component) */ - double getDynamicPower() const { - return dyn_expr.eval( - std::bind(&MathExprPowerModel::getStatValue, - this, std::placeholders::_1) - ); - } + double getDynamicPower() const { return eval(dyn_expr); } /** * Get the static power consumption. * * @return Power (Watts) consumed by this object (static component) */ - double getStaticPower() const { - return st_expr.eval( - std::bind(&MathExprPowerModel::getStatValue, - this, std::placeholders::_1) - ); - } + double getStaticPower() const { return eval(st_expr); } /** * Get the value for a variable (maps to a stat) @@ -99,6 +89,23 @@ class MathExprPowerModel : public PowerModelState void regStats(); private: + /** + * Evaluate an expression in the context of this object, fatal if + * evaluation fails. + * + * @param expr Expression to evaluate + * @return Value of expression. + */ + double eval(const MathExpr &expr) const; + + /** + * Evaluate an expression in the context of this object, set + * failed if evaluation failed. + * + * @param expr Expression to evaluate + * @return Value of expression. + */ + double tryEval(const MathExpr &expr) const; // Math expressions for dynamic and static power MathExpr dyn_expr, st_expr; @@ -108,6 +115,10 @@ class MathExprPowerModel : public PowerModelState // Map that contains relevant stats for this power model std::unordered_map stats_map; + + // Did the expression fail to evaluate (e.g., because a stat value + // can't be resolved) + mutable bool failed; }; #endif -- cgit v1.2.3