[Lldb-commits] [lldb] 77e9d10 - [lldb] Assert filecache and live memory match on debug under a setting
Augusto Noronha via lldb-commits
lldb-commits at lists.llvm.org
Thu Jul 29 06:31:28 PDT 2021
Author: Augusto Noronha
Date: 2021-07-29T10:29:34-03:00
New Revision: 77e9d10f0fbfe04a14e6ce61753376dd78e0c2f0
URL: https://github.com/llvm/llvm-project/commit/77e9d10f0fbfe04a14e6ce61753376dd78e0c2f0
DIFF: https://github.com/llvm/llvm-project/commit/77e9d10f0fbfe04a14e6ce61753376dd78e0c2f0.diff
LOG: [lldb] Assert filecache and live memory match on debug under a setting
Added:
Modified:
lldb/include/lldb/Core/Section.h
lldb/include/lldb/Target/Target.h
lldb/packages/Python/lldbsuite/test/lldbtest.py
lldb/source/Core/Section.cpp
lldb/source/Target/Target.cpp
lldb/source/Target/TargetProperties.td
lldb/test/Shell/lit-lldb-init.in
Removed:
################################################################################
diff --git a/lldb/include/lldb/Core/Section.h b/lldb/include/lldb/Core/Section.h
index 3d4ab154e743f..3914469aafc1a 100644
--- a/lldb/include/lldb/Core/Section.h
+++ b/lldb/include/lldb/Core/Section.h
@@ -236,6 +236,8 @@ class Section : public std::enable_shared_from_this<Section>,
void SetIsRelocated(bool b) { m_relocated = b; }
+ bool IsReadOnly();
+
protected:
ObjectFile *m_obj_file; // The object file that data for this section should
// be read from
diff --git a/lldb/include/lldb/Target/Target.h b/lldb/include/lldb/Target/Target.h
index ac8d002b09a12..d15370259f467 100644
--- a/lldb/include/lldb/Target/Target.h
+++ b/lldb/include/lldb/Target/Target.h
@@ -229,6 +229,10 @@ class TargetProperties : public Properties {
bool GetDebugUtilityExpression() const;
+ void SetVerifyFileCacheMemoryReads(bool debug);
+
+ bool GetVerifyFileCacheMemoryReads() const;
+
private:
// Callbacks for m_launch_info.
void Arg0ValueChangedCallback();
diff --git a/lldb/packages/Python/lldbsuite/test/lldbtest.py b/lldb/packages/Python/lldbsuite/test/lldbtest.py
index 7e1fdce36ede6..366c40db81507 100644
--- a/lldb/packages/Python/lldbsuite/test/lldbtest.py
+++ b/lldb/packages/Python/lldbsuite/test/lldbtest.py
@@ -798,6 +798,9 @@ def setUpCommands(cls):
'settings set symbols.clang-modules-cache-path "{}"'.format(
configuration.lldb_module_cache_dir),
"settings set use-color false",
+
+ # Verify that file cache and live memory always match.
+ "settings set target.verify-file-cache-memory-reads true",
]
# Set any user-overridden settings.
diff --git a/lldb/source/Core/Section.cpp b/lldb/source/Core/Section.cpp
index a5a10141aa649..af5cee2f9b9b9 100644
--- a/lldb/source/Core/Section.cpp
+++ b/lldb/source/Core/Section.cpp
@@ -599,3 +599,9 @@ size_t SectionList::Slide(addr_t slide_amount, bool slide_children) {
}
return count;
}
+
+bool Section::IsReadOnly() {
+ auto permissions = Flags(GetPermissions());
+ return !permissions.Test(ePermissionsWritable) &&
+ permissions.Test(ePermissionsReadable);
+}
diff --git a/lldb/source/Target/Target.cpp b/lldb/source/Target/Target.cpp
index 1f8e8c54fa9e1..33691e8e97856 100644
--- a/lldb/source/Target/Target.cpp
+++ b/lldb/source/Target/Target.cpp
@@ -1763,21 +1763,34 @@ size_t Target::ReadMemory(const Address &addr, void *dst, size_t dst_len,
// Read from file cache if read-only section.
if (!force_live_memory && resolved_addr.IsSectionOffset()) {
SectionSP section_sp(resolved_addr.GetSection());
- if (section_sp) {
- auto permissions = Flags(section_sp->GetPermissions());
- bool is_readonly = !permissions.Test(ePermissionsWritable) &&
- permissions.Test(ePermissionsReadable);
- if (is_readonly) {
- file_cache_bytes_read =
- ReadMemoryFromFileCache(resolved_addr, dst, dst_len, error);
- if (file_cache_bytes_read == dst_len)
- return file_cache_bytes_read;
- else if (file_cache_bytes_read > 0) {
- file_cache_read_buffer =
- std::make_unique<uint8_t[]>(file_cache_bytes_read);
- std::memcpy(file_cache_read_buffer.get(), dst, file_cache_bytes_read);
+ if (section_sp && section_sp->IsReadOnly()) {
+ file_cache_bytes_read =
+ ReadMemoryFromFileCache(resolved_addr, dst, dst_len, error);
+
+ if (GetVerifyFileCacheMemoryReads()) {
+ if (ProcessIsValid() && file_cache_bytes_read == dst_len) {
+ if (load_addr == LLDB_INVALID_ADDRESS)
+ load_addr = resolved_addr.GetLoadAddress(this);
+ if (load_addr != LLDB_INVALID_ADDRESS) {
+ std::unique_ptr<uint8_t[]> live_buf =
+ std::make_unique<uint8_t[]>(dst_len);
+ bytes_read = m_process_sp->ReadMemory(load_addr, live_buf.get(),
+ dst_len, error);
+ if (bytes_read == dst_len) {
+ lldbassert(memcmp(live_buf.get(), dst, dst_len) == 0 &&
+ "File cache and live memory diverge!");
+ }
+ }
}
}
+
+ if (file_cache_bytes_read == dst_len)
+ return file_cache_bytes_read;
+ if (file_cache_bytes_read > 0) {
+ file_cache_read_buffer =
+ std::make_unique<uint8_t[]>(file_cache_bytes_read);
+ std::memcpy(file_cache_read_buffer.get(), dst, file_cache_bytes_read);
+ }
}
}
@@ -4376,6 +4389,17 @@ void TargetProperties::SetDebugUtilityExpression(bool debug) {
m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, debug);
}
+bool TargetProperties::GetVerifyFileCacheMemoryReads() const {
+ const uint32_t idx = ePropertyVerifyFileCacheMemoryReads;
+ return m_collection_sp->GetPropertyAtIndexAsBoolean(
+ nullptr, idx, g_target_properties[idx].default_uint_value != 0);
+}
+
+void TargetProperties::SetVerifyFileCacheMemoryReads(bool verify) {
+ const uint32_t idx = ePropertyVerifyFileCacheMemoryReads;
+ m_collection_sp->SetPropertyAtIndexAsBoolean(nullptr, idx, verify);
+}
+
// Target::TargetEventData
Target::TargetEventData::TargetEventData(const lldb::TargetSP &target_sp)
diff --git a/lldb/source/Target/TargetProperties.td b/lldb/source/Target/TargetProperties.td
index 8f627ad0f1a86..bce426884a7d2 100644
--- a/lldb/source/Target/TargetProperties.td
+++ b/lldb/source/Target/TargetProperties.td
@@ -175,6 +175,9 @@ let Definition = "target" in {
def DebugUtilityExpression: Property<"debug-utility-expression", "Boolean">,
DefaultFalse,
Desc<"Enable debugging of LLDB-internal utility expressions.">;
+ def VerifyFileCacheMemoryReads: Property<"verify-file-cache-memory-reads", "Boolean">,
+ DefaultFalse,
+ Desc<"Verify that memory read from the file-cache is identical to the memory read from the process.">;
}
let Definition = "process_experimental" in {
diff --git a/lldb/test/Shell/lit-lldb-init.in b/lldb/test/Shell/lit-lldb-init.in
index 6d3b5fefb3bd3..60670c5357421 100644
--- a/lldb/test/Shell/lit-lldb-init.in
+++ b/lldb/test/Shell/lit-lldb-init.in
@@ -6,3 +6,4 @@ settings set symbols.clang-modules-cache-path "@LLDB_TEST_MODULE_CACHE_LLDB@"
settings set target.auto-apply-fixits false
settings set target.inherit-tcc true
settings set target.detach-on-error false
+settings set target.verify-file-cache-memory-reads true
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