Subzero: Allow per-method controls.

src/IceRangeSpec.cpp

+//===- subzero/src/IceRangeSpec.cpp - Include/exclude specification -------===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief Implements a class for specifying sets of names and number ranges to
+/// match against.  This is specified as a comma-separated list of clauses.
+/// Each clause optionally starts with '-' to indicate exclusion instead of
+/// inclusion.  A clause can be a name, or a numeric range X:Y, or a single
+/// number X.  The X:Y form indicates a range of numbers greater than or equal
+/// to X and strictly less than Y.  A missing "X" is taken to be 0, and a
+/// missing "Y" is taken to be infinite.  E.g., "0:" and ":" specify the entire
+/// set.
+///
+/// This is essentially the same implementation as in szbuild.py, except that
+/// regular expressions are not used for the names.
+///
+//===----------------------------------------------------------------------===//
+
+#include "IceRangeSpec.h"
+#include "IceStringPool.h"
+
+#include <cctype>
+#include <string>
+#include <unordered_set>
+#include <vector>
+
+namespace Ice {
+
+bool RangeSpec::HasNames = false;
+
+namespace {
+
+/// Helper function to tokenize a string into a vector of string tokens, given a
+/// single delimiter character.  An empty string produces an empty token vector.
+/// Zero-length tokens are allowed, e.g. ",a,,,b," may tokenize to
+/// {"","a","","","b",""}.
+std::vector<std::string> tokenize(const std::string &Spec, char Delimiter) {
+  std::vector<std::string> Tokens;
+  if (!Spec.empty()) {
+    std::string::size_type StartPos = 0;
+    std::string::size_type DelimPos = 0;
+    while (DelimPos != std::string::npos) {
+      DelimPos = Spec.find(Delimiter, StartPos);
+      Tokens.emplace_back(Spec.substr(StartPos, DelimPos - StartPos));
+      StartPos = DelimPos + 1;
+    }
+  }
+  return Tokens;
+}
+
+/// Helper function to parse "X" or "X:Y" into First and Last.
+/// - "X" is treated as "X:X+1".
+/// - ":Y" is treated as "0:Y".
+/// - "X:" is treated as "X:inf"
+///
+/// Behavior is undefined if "X" or "Y" is not a proper number (since std::stoul
+/// throws an exception).
+///
+/// If the string doesn't contain 1 or 2 ':' delimiters, or X>=Y,
+/// report_fatal_error is called.
+void getRange(const std::string &Token, uint32_t *First, uint32_t *Last) {
+  bool Error = false;
+  auto Tokens = tokenize(Token, RangeSpec::DELIM_RANGE);
+  if (Tokens.size() == 1) {
+    *First = std::stoul(Tokens[0]);
+    *Last = *First + 1;
+  } else if (Tokens.size() == 2) {
+    *First = Tokens[0].empty() ? 0 : std::stoul(Tokens[0]);
+    *Last = Tokens[1].empty() ? RangeSpec::RangeMax : std::stoul(Tokens[1]);
+  } else {
+    Error = true;
+  }
+  if (*First >= *Last) {
+    Error = true;
+  }
+  if (Error) {
+    llvm::report_fatal_error("Invalid range " + Token);
+  }
+}
+
+/// Helper function to add one token to the include or exclude set.  The token
+/// is examined and then treated as either a numeric range or a single name.
+void record(const std::string &Token, RangeSpec::Desc *D) {
+  if (Token.empty())
+    return;
+  // Mark that an include or exclude was explicitly given.  This affects the
+  // default decision when matching a value that wasn't explicitly provided in
+  // the include or exclude list.
+  D->IsExplicit = true;
+  // A range is identified by starting with a digit or a ':'.
+  if (Token[0] == RangeSpec::DELIM_RANGE || std::isdigit(Token[0])) {
+    uint32_t First, Last;
+    getRange(Token, &First, &Last);
+    if (Last == RangeSpec::RangeMax) {
+      D->AllFrom = std::min(D->AllFrom, First);
+    } else {
+      if (Last >= D->Numbers.size())
+        D->Numbers.resize(Last + 1);
+      D->Numbers.set(First, Last);
+    }
+  } else {
+    // Otherwise treat it as a single name.
+    D->Names.insert(Token);
+  }
+}
+
+} // end of anonymous namespace
+
+/// Initialize the RangeSpec with the given string.  Calling init multiple times
+/// (e.g. init("A");init("B");) is equivalent to init("A,B"); .
+void RangeSpec::init(const std::string &Spec) {
+  auto Tokens = tokenize(Spec, DELIM_LIST);
+  for (const auto &Token : Tokens) {
+    if (Token[0] == '-') {
+      exclude(Token.substr(1));
+    } else {
+      include(Token);
+    }
+  }
+  if (!Includes.Names.empty() || !Excludes.Names.empty())
+    HasNames = true;
+}
+
+/// Determine whether the given Name/Number combo match the specification given
+/// to the init() method.  Explicit excludes take precedence over explicit
+/// includes.  If the combo doesn't match any explicit include or exclude:
+/// - false if the init() string is empty (no explicit includes or excludes)
+/// - true if there is at least one explicit exclude and no explicit includes
+/// - false otherwise (at least one explicit include)
+bool RangeSpec::match(const std::string &Name, uint32_t Number) const {
+  // No match if it is explicitly excluded by name or number.
+  if (Excludes.Names.find(Name) != Excludes.Names.end())
+    return false;
+  if (Number >= Excludes.AllFrom)
+    return false;
+  if (Number < Excludes.Numbers.size() && Excludes.Numbers[Number])
+    return false;
+
+  // Positive match if it is explicitly included by name or number.
+  if (Includes.Names.find(Name) != Includes.Names.end())
+    return true;
+  if (Number >= Includes.AllFrom)
+    return true;
+  if (Number < Includes.Numbers.size() && Includes.Numbers[Number])
+    return true;
+
+  // Otherwise use the default decision.
+  return Excludes.IsExplicit && !Includes.IsExplicit;
+}
+
+void RangeSpec::include(const std::string &Token) { record(Token, &Includes); }
+
+void RangeSpec::exclude(const std::string &Token) { record(Token, &Excludes); }
+
+} // end of namespace Ice