[lldb] Add --all option to "memory region"

This adds an option to the memory region command
to print all regions at once. Like you can do by
starting at address 0 and repeating the command
manually.

memory region [-a] [<address-expression>]

(lldb) memory region --all
[0x0000000000000000-0x0000000000400000) ---
[0x0000000000400000-0x0000000000401000) r-x <...>/a.out PT_LOAD[0]
<...>
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0001000000000000-0xffffffffffffffff) ---

The output matches exactly what you'd get from
repeating the command. Including that it shows
unmapped areas between the mapped regions.

(this is why Process GetMemoryRegions is not
used, that skips unmapped areas)

Help text has been updated to show that you can have
an address or --all but not both.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D111791

lldb/source/Commands/CommandObjectMemory.cpp

@@ -1641,19 +1641,117 @@ protected:
 // CommandObjectMemoryRegion
 #pragma mark CommandObjectMemoryRegion
 
+#define LLDB_OPTIONS_memory_region
+#include "CommandOptions.inc"
+
 class CommandObjectMemoryRegion : public CommandObjectParsed {
 public:
+  class OptionGroupMemoryRegion : public OptionGroup {
+  public:
+    OptionGroupMemoryRegion() : OptionGroup(), m_all(false, false) {}
+
+    ~OptionGroupMemoryRegion() override = default;
+
+    llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
+      return llvm::makeArrayRef(g_memory_region_options);
+    }
+
+    Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_value,
+                          ExecutionContext *execution_context) override {
+      Status status;
+      const int short_option = g_memory_region_options[option_idx].short_option;
+
+      switch (short_option) {
+      case 'a':
+        m_all.SetCurrentValue(true);
+        m_all.SetOptionWasSet();
+        break;
+      default:
+        llvm_unreachable("Unimplemented option");
+      }
+
+      return status;
+    }
+
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      m_all.Clear();
+    }
+
+    OptionValueBoolean m_all;
+  };
+
   CommandObjectMemoryRegion(CommandInterpreter &interpreter)
       : CommandObjectParsed(interpreter, "memory region",
                             "Get information on the memory region containing "
                             "an address in the current target process.",
-                            "memory region ADDR",
+                            "memory region <address-expression> (or --all)",
                             eCommandRequiresProcess | eCommandTryTargetAPILock |
-                                eCommandProcessMustBeLaunched) {}
+                                eCommandProcessMustBeLaunched) {
+    // Address in option set 1.
+    m_arguments.push_back(CommandArgumentEntry{CommandArgumentData(
+        eArgTypeAddressOrExpression, eArgRepeatPlain, LLDB_OPT_SET_1)});
+    // "--all" will go in option set 2.
+    m_option_group.Append(&m_memory_region_options);
+    m_option_group.Finalize();
+  }
 
   ~CommandObjectMemoryRegion() override = default;
 
+  Options *GetOptions() override { return &m_option_group; }
+
 protected:
+  void DumpRegion(CommandReturnObject &result, Target &target,
+                  const MemoryRegionInfo &range_info, lldb::addr_t load_addr) {
+    lldb::addr_t resolve_addr = load_addr;
+    if (m_memory_region_options.m_all)
+      resolve_addr = range_info.GetRange().GetRangeBase();
+
+    lldb_private::Address addr;
+    ConstString section_name;
+    if (target.ResolveLoadAddress(resolve_addr, addr)) {
+      SectionSP section_sp(addr.GetSection());
+      if (section_sp) {
+        // Got the top most section, not the deepest section
+        while (section_sp->GetParent())
+          section_sp = section_sp->GetParent();
+        section_name = section_sp->GetName();
+      }
+    }
+
+    ConstString name = range_info.GetName();
+    result.AppendMessageWithFormatv(
+        "[{0:x16}-{1:x16}) {2:r}{3:w}{4:x}{5}{6}{7}{8}",
+        range_info.GetRange().GetRangeBase(),
+        range_info.GetRange().GetRangeEnd(), range_info.GetReadable(),
+        range_info.GetWritable(), range_info.GetExecutable(), name ? " " : "",
+        name, section_name ? " " : "", section_name);
+    MemoryRegionInfo::OptionalBool memory_tagged = range_info.GetMemoryTagged();
+    if (memory_tagged == MemoryRegionInfo::OptionalBool::eYes)
+      result.AppendMessage("memory tagging: enabled");
+
+    const llvm::Optional<std::vector<addr_t>> &dirty_page_list =
+        range_info.GetDirtyPageList();
+    if (dirty_page_list.hasValue()) {
+      const size_t page_count = dirty_page_list.getValue().size();
+      result.AppendMessageWithFormat(
+          "Modified memory (dirty) page list provided, %zu entries.\n",
+          page_count);
+      if (page_count > 0) {
+        bool print_comma = false;
+        result.AppendMessageWithFormat("Dirty pages: ");
+        for (size_t i = 0; i < page_count; i++) {
+          if (print_comma)
+            result.AppendMessageWithFormat(", ");
+          else
+            print_comma = true;
+          result.AppendMessageWithFormat("0x%" PRIx64,
+                                         dirty_page_list.getValue()[i]);
+        }
+        result.AppendMessageWithFormat(".\n");
+      }
+    }
+  }
+
   bool DoExecute(Args &command, CommandReturnObject &result) override {
     ProcessSP process_sp = m_exe_ctx.GetProcessSP();
     if (!process_sp) {
@@ -1670,6 +1768,13 @@ protected:
     const lldb::ABISP &abi = process_sp->GetABI();
 
     if (argc == 1) {
+      if (m_memory_region_options.m_all) {
+        result.AppendError(
+            "The \"--all\" option cannot be used when an address "
+            "argument is given");
+        return false;
+      }
+
       auto load_addr_str = command[0].ref();
       // Non-address bits in this will be handled later by GetMemoryRegion
       load_addr = OptionArgParser::ToAddress(&m_exe_ctx, load_addr_str,
@@ -1683,67 +1788,53 @@ protected:
                // When we're repeating the command, the previous end address is
                // used for load_addr. If that was 0xF...F then we must have
                // reached the end of memory.
-               (argc == 0 && load_addr == LLDB_INVALID_ADDRESS) ||
+               (argc == 0 && !m_memory_region_options.m_all &&
+                load_addr == LLDB_INVALID_ADDRESS) ||
                // If the target has non-address bits (tags, limited virtual
                // address size, etc.), the end of mappable memory will be lower
                // than that. So if we find any non-address bit set, we must be
                // at the end of the mappable range.
                (abi && (abi->FixAnyAddress(load_addr) != load_addr))) {
-      result.AppendErrorWithFormat("'%s' takes one argument:\nUsage: %s\n",
-                                   m_cmd_name.c_str(), m_cmd_syntax.c_str());
+      result.AppendErrorWithFormat(
+          "'%s' takes one argument or \"--all\" option:\nUsage: %s\n",
+          m_cmd_name.c_str(), m_cmd_syntax.c_str());
       return false;
     }
 
-    lldb_private::MemoryRegionInfo range_info;
-    error = process_sp->GetMemoryRegionInfo(load_addr, range_info);
+    lldb_private::MemoryRegionInfos region_list;
+    if (m_memory_region_options.m_all) {
+      // We don't use GetMemoryRegions here because it doesn't include unmapped
+      // areas like repeating the command would. So instead, emulate doing that.
+      lldb::addr_t addr = 0;
+      while (error.Success() && addr != LLDB_INVALID_ADDRESS &&
+             // When there are non-address bits the last range will not extend
+             // to LLDB_INVALID_ADDRESS but to the max virtual address.
+             // This prevents us looping forever if that is the case.
+             (abi && (abi->FixAnyAddress(addr) == addr))) {
+        lldb_private::MemoryRegionInfo region_info;
+        error = process_sp->GetMemoryRegionInfo(addr, region_info);
+
+        if (error.Success()) {
+          region_list.push_back(region_info);
+          addr = region_info.GetRange().GetRangeEnd();
+        }
+      }
+
+      // Even if we read nothing, don't error for --all
+      error.Clear();
+    } else {
+      lldb_private::MemoryRegionInfo region_info;
+      error = process_sp->GetMemoryRegionInfo(load_addr, region_info);
+      if (error.Success())
+        region_list.push_back(region_info);
+    }
+
     if (error.Success()) {
-      lldb_private::Address addr;
-      ConstString name = range_info.GetName();
-      ConstString section_name;
-      if (process_sp->GetTarget().ResolveLoadAddress(load_addr, addr)) {
-        SectionSP section_sp(addr.GetSection());
-        if (section_sp) {
-          // Got the top most section, not the deepest section
-          while (section_sp->GetParent())
-            section_sp = section_sp->GetParent();
-          section_name = section_sp->GetName();
-        }
+      for (MemoryRegionInfo &range_info : region_list) {
+        DumpRegion(result, process_sp->GetTarget(), range_info, load_addr);
+        m_prev_end_addr = range_info.GetRange().GetRangeEnd();
       }
 
-      result.AppendMessageWithFormatv(
-          "[{0:x16}-{1:x16}) {2:r}{3:w}{4:x}{5}{6}{7}{8}",
-          range_info.GetRange().GetRangeBase(),
-          range_info.GetRange().GetRangeEnd(), range_info.GetReadable(),
-          range_info.GetWritable(), range_info.GetExecutable(), name ? " " : "",
-          name, section_name ? " " : "", section_name);
-      MemoryRegionInfo::OptionalBool memory_tagged =
-          range_info.GetMemoryTagged();
-      if (memory_tagged == MemoryRegionInfo::OptionalBool::eYes)
-        result.AppendMessage("memory tagging: enabled");
-
-      const llvm::Optional<std::vector<addr_t>> &dirty_page_list =
-          range_info.GetDirtyPageList();
-      if (dirty_page_list.hasValue()) {
-        const size_t page_count = dirty_page_list.getValue().size();
-        result.AppendMessageWithFormat(
-            "Modified memory (dirty) page list provided, %zu entries.\n",
-            page_count);
-        if (page_count > 0) {
-          bool print_comma = false;
-          result.AppendMessageWithFormat("Dirty pages: ");
-          for (size_t i = 0; i < page_count; i++) {
-            if (print_comma)
-              result.AppendMessageWithFormat(", ");
-            else
-              print_comma = true;
-            result.AppendMessageWithFormat("0x%" PRIx64,
-                                           dirty_page_list.getValue()[i]);
-          }
-          result.AppendMessageWithFormat(".\n");
-        }
-      }
-
-      m_prev_end_addr = range_info.GetRange().GetRangeEnd();
       result.SetStatus(eReturnStatusSuccessFinishResult);
       return true;
     }
@@ -1760,6 +1851,9 @@ protected:
   }
 
   lldb::addr_t m_prev_end_addr = LLDB_INVALID_ADDRESS;
+
+  OptionGroupOptions m_option_group;
+  OptionGroupMemoryRegion m_memory_region_options;
 };
 
 // CommandObjectMemory

lldb/source/Commands/Options.td

@@ -515,6 +515,12 @@ let Command = "memory write" in {
     Desc<"Start writing bytes from an offset within the input file.">;
 }
 
+let Command = "memory region" in {
+  def memory_region_all : Option<"all", "a">, Group<2>, Required,
+    Desc<"Show all memory regions. This is equivalent to starting from address "
+         "0 and repeating the command. Unmapped areas are included.">;
+}
+
 let Command = "memory tag write" in {
   def memory_write_end_addr : Option<"end-addr", "e">, Group<1>,
   Arg<"AddressOrExpression">, Desc<

lldb/test/API/functionalities/memory-region/TestMemoryRegion.py

@@ -23,6 +23,12 @@ class MemoryCommandRegion(TestBase):
             'main.cpp',
             '// Run here before printing memory regions')
 
+    def test_help(self):
+        """ Test that help shows you must have one of address or --all, not both."""
+        self.expect("help memory region",
+            substrs=["memory region <address-expression>",
+                     "memory region -a"])
+
     def test(self):
         self.build()
 
@@ -39,7 +45,15 @@ class MemoryCommandRegion(TestBase):
         # Test that the first 'memory region' command prints the usage.
         interp.HandleCommand("memory region", result)
         self.assertFalse(result.Succeeded())
-        self.assertRegexpMatches(result.GetError(), "Usage: memory region ADDR")
+        self.assertEqual(result.GetError(),
+                    "error: 'memory region' takes one argument or \"--all\" option:\n"
+                    "Usage: memory region <address-expression> (or --all)\n")
+
+        # We allow --all or an address argument, not both
+        interp.HandleCommand("memory region --all 0", result)
+        self.assertFalse(result.Succeeded())
+        self.assertRegexpMatches(result.GetError(),
+                "The \"--all\" option cannot be used when an address argument is given")
 
         # Test that when the address fails to parse, we show an error and do not continue
         interp.HandleCommand("memory region not_an_address", result)
@@ -47,18 +61,28 @@ class MemoryCommandRegion(TestBase):
         self.assertEqual(result.GetError(),
                 "error: invalid address argument \"not_an_address\": address expression \"not_an_address\" evaluation failed\n")
 
+        # Accumulate the results to compare with the --all output
+        all_regions = ""
+
         # Now let's print the memory region starting at 0 which should always work.
         interp.HandleCommand("memory region 0x0", result)
         self.assertTrue(result.Succeeded())
         self.assertRegexpMatches(result.GetOutput(), "\\[0x0+-")
+        all_regions += result.GetOutput()
 
         # Keep printing memory regions until we printed all of them.
         while True:
             interp.HandleCommand("memory region", result)
             if not result.Succeeded():
                 break
+            all_regions += result.GetOutput()
 
         # Now that we reached the end, 'memory region' should again print the usage.
         interp.HandleCommand("memory region", result)
         self.assertFalse(result.Succeeded())
-        self.assertRegexpMatches(result.GetError(), "Usage: memory region ADDR")
+        self.assertRegexpMatches(result.GetError(), "Usage: memory region <address\-expression> \(or \-\-all\)")
+
+        # --all should match what repeating the command gives you
+        interp.HandleCommand("memory region --all", result)
+        self.assertTrue(result.Succeeded())
+        self.assertEqual(result.GetOutput(), all_regions)

lldb/test/API/linux/aarch64/tagged_memory_region/TestAArch64LinuxTaggedMemoryRegion.py

@@ -55,7 +55,7 @@ class AArch64LinuxTaggedMemoryRegionTestCase(TestBase):
             if result.Succeeded():
                 repeats += 1
             else:
-                self.assertRegexpMatches(result.GetError(), "Usage: memory region ADDR")
+                self.assertRegexpMatches(result.GetError(), "Usage: memory region")
                 break
 
         # This time repeat until we get the last region. At that

llvm/docs/ReleaseNotes.rst

@@ -170,6 +170,11 @@ Changes to the LLVM tools
 Changes to LLDB
 ---------------------------------
 
+* The "memory region" command now has a "--all" option to list all
+  memory regions (including unmapped ranges). This is the equivalent
+  of using address 0 then repeating the command until all regions
+  have been listed.
+
 Changes to Sanitizers
 ---------------------