[llvm] [OptBisect] Add support for selecting ranges of passes and refactor DebugCounter to use a shared Range API. (PR #152393)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,153 @@
+//===- llvm/Support/Range.cpp - Range parsing utility ---------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Range.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/Regex.h"
+#include "llvm/Support/raw_ostream.h"
+#include <sstream>
+
+using namespace llvm;
+
+Expected<RangeUtils::RangeList> RangeUtils::parseRanges(const StringRef Str,
+                                                        const char Separator) {
+  RangeList Ranges;
+
+  if (Str.empty())
+    return std::move(Ranges);
+
+  // Split by the specified separator
+  SmallVector<StringRef, 8> Parts;
+  Str.split(Parts, Separator, -1, false);
+
+  // Regex to match either single number or range "num1-num2"
+  const Regex RangeRegex("^([0-9]+)(-([0-9]+))?$");
+
+  for (StringRef Part : Parts) {
+    Part = Part.trim();
+    if (Part.empty())
+      continue;
+
+    SmallVector<StringRef, 4> Matches;
+    if (!RangeRegex.match(Part, &Matches))
+      return createStringError(std::errc::invalid_argument,
+                               "Invalid range format: '%s'",
+                               Part.str().c_str());
+
+    int64_t Begin, End;
+    if (Matches[1].getAsInteger(10, Begin))
+      return createStringError(std::errc::invalid_argument,
+                               "Failed to parse number: '%s'",
+                               Matches[1].str().c_str());
+
+    if (!Matches[3].empty()) {
+      // Range format "begin-end"
+      if (Matches[3].getAsInteger(10, End))
+        return createStringError(std::errc::invalid_argument,
+                                 "Failed to parse number: '%s'",
+                                 Matches[3].str().c_str());
+      if (Begin >= End)
+        return createStringError(std::errc::invalid_argument,
+                                 "Invalid range: %lld >= %lld", Begin, End);
+    } else
+      // Single number
+      End = Begin;
+
+    // Check ordering constraint (ranges must be in increasing order)
+    if (!Ranges.empty() && Begin <= Ranges.back().End)
+      return createStringError(
+          std::errc::invalid_argument,
+          "Expected ranges to be in increasing order: %lld <= %lld", Begin,
+          Ranges.back().End);
+
+    Ranges.push_back(Range(Begin, End));
+  }
+
+  return std::move(Ranges);
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nikic wrote:

Shouldn't need std::move here due to NRVO?

https://github.com/llvm/llvm-project/pull/152393