[LLDB] Update DIL handling of array subscripting. (#151605)
This updates the DIL code for handling array subscripting to more
closely match and handle all the cases from the original 'frame var'
implementation. Also updates the DIL array subscripting test. This
particularly fixes some issues with handling synthetic children, objc
pointers, and accessing specific bits within scalar data types.
diff --git a/lldb/source/ValueObject/DILEval.cpp b/lldb/source/ValueObject/DILEval.cpp
index 6f28434..89a117e 100644
--- a/lldb/source/ValueObject/DILEval.cpp
+++ b/lldb/source/ValueObject/DILEval.cpp
@@ -330,40 +330,83 @@
return lhs_or_err;
lldb::ValueObjectSP base = *lhs_or_err;
- // Check to see if 'base' has a synthetic value; if so, try using that.
+ StreamString var_expr_path_strm;
uint64_t child_idx = node->GetIndex();
- if (lldb::ValueObjectSP synthetic = base->GetSyntheticValue()) {
- llvm::Expected<uint32_t> num_children =
- synthetic->GetNumChildren(child_idx + 1);
- if (!num_children)
- return llvm::make_error<DILDiagnosticError>(
- m_expr, toString(num_children.takeError()), node->GetLocation());
- if (child_idx >= *num_children) {
- std::string message = llvm::formatv(
- "array index {0} is not valid for \"({1}) {2}\"", child_idx,
- base->GetTypeName().AsCString("<invalid type>"),
- base->GetName().AsCString());
- return llvm::make_error<DILDiagnosticError>(m_expr, message,
+ lldb::ValueObjectSP child_valobj_sp;
+ bool is_incomplete_array = false;
+ CompilerType base_type = base->GetCompilerType().GetNonReferenceType();
+ base->GetExpressionPath(var_expr_path_strm);
+ if (base_type.IsPointerType()) {
+ child_valobj_sp = base->GetSyntheticArrayMember(child_idx, true);
+ if (!child_valobj_sp) {
+ std::string err_msg = llvm::formatv(
+ "failed to use pointer as array for index {0} for "
+ "\"({1}) {2}\"",
+ child_idx, base->GetTypeName().AsCString("<invalid type>"),
+ var_expr_path_strm.GetData());
+ if (base_type.IsPointerToVoid())
+ err_msg = "subscript of pointer to incomplete type 'void'";
+ return llvm::make_error<DILDiagnosticError>(m_expr, std::move(err_msg),
node->GetLocation());
}
- if (lldb::ValueObjectSP child_valobj_sp =
- synthetic->GetChildAtIndex(child_idx))
- return child_valobj_sp;
+ } else if (base_type.IsArrayType(nullptr, nullptr, &is_incomplete_array)) {
+ child_valobj_sp = base->GetChildAtIndex(child_idx);
+ if (!child_valobj_sp && (is_incomplete_array || m_use_synthetic))
+ child_valobj_sp = base->GetSyntheticArrayMember(child_idx, true);
+ if (!child_valobj_sp) {
+ std::string err_msg = llvm::formatv(
+ "array index {0} is not valid for \"({1}) {2}\"", child_idx,
+ base->GetTypeName().AsCString("<invalid type>"),
+ var_expr_path_strm.GetData());
+ return llvm::make_error<DILDiagnosticError>(m_expr, std::move(err_msg),
+ node->GetLocation());
+ }
+ } else if (base_type.IsScalarType()) {
+ child_valobj_sp =
+ base->GetSyntheticBitFieldChild(child_idx, child_idx, true);
+ if (!child_valobj_sp) {
+ std::string err_msg = llvm::formatv(
+ "bitfield range {0}-{1} is not valid for \"({2}) {3}\"", child_idx,
+ child_idx, base->GetTypeName().AsCString("<invalid type>"),
+ var_expr_path_strm.GetData());
+ return llvm::make_error<DILDiagnosticError>(m_expr, std::move(err_msg),
+ node->GetLocation(), 1);
+ }
+ } else {
+ lldb::ValueObjectSP synthetic = base->GetSyntheticValue();
+ if (!m_use_synthetic || !synthetic || synthetic == base) {
+ std::string err_msg =
+ llvm::formatv("\"{0}\" is not an array type",
+ base->GetTypeName().AsCString("<invalid type>"));
+ return llvm::make_error<DILDiagnosticError>(m_expr, std::move(err_msg),
+ node->GetLocation(), 1);
+ }
+ if (static_cast<uint32_t>(child_idx) >=
+ synthetic->GetNumChildrenIgnoringErrors(child_idx + 1)) {
+ std::string err_msg = llvm::formatv(
+ "array index {0} is not valid for \"({1}) {2}\"", child_idx,
+ base->GetTypeName().AsCString("<invalid type>"),
+ var_expr_path_strm.GetData());
+ return llvm::make_error<DILDiagnosticError>(m_expr, std::move(err_msg),
+ node->GetLocation(), 1);
+ }
+ child_valobj_sp = synthetic->GetChildAtIndex(child_idx);
+ if (!child_valobj_sp) {
+ std::string err_msg = llvm::formatv(
+ "array index {0} is not valid for \"({1}) {2}\"", child_idx,
+ base->GetTypeName().AsCString("<invalid type>"),
+ var_expr_path_strm.GetData());
+ return llvm::make_error<DILDiagnosticError>(m_expr, std::move(err_msg),
+ node->GetLocation(), 1);
+ }
}
- auto base_type = base->GetCompilerType().GetNonReferenceType();
- if (!base_type.IsPointerType() && !base_type.IsArrayType())
- return llvm::make_error<DILDiagnosticError>(
- m_expr, "subscripted value is not an array or pointer",
- node->GetLocation());
- if (base_type.IsPointerToVoid())
- return llvm::make_error<DILDiagnosticError>(
- m_expr, "subscript of pointer to incomplete type 'void'",
- node->GetLocation());
-
- if (base_type.IsArrayType()) {
- if (lldb::ValueObjectSP child_valobj_sp = base->GetChildAtIndex(child_idx))
- return child_valobj_sp;
+ if (child_valobj_sp) {
+ if (m_use_dynamic != lldb::eNoDynamicValues) {
+ if (auto dynamic_sp = child_valobj_sp->GetDynamicValue(m_use_dynamic))
+ child_valobj_sp = std::move(dynamic_sp);
+ }
+ return child_valobj_sp;
}
int64_t signed_child_idx = node->GetIndex();
diff --git a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py
index 0f56057..e3cfb87 100644
--- a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py
+++ b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py
@@ -69,17 +69,18 @@
substrs=["expected 'r_square', got: <'.'"],
)
- # Base should be a "pointer to T" and index should be of an integral type.
- self.expect(
- "frame var 'idx_1[0]'",
- error=True,
- substrs=["subscripted value is not an array or pointer"],
- )
+ # Test accessing bits in scalar types.
+ self.expect_var_path("idx_1[0]", value="1")
+ self.expect_var_path("idx_1[1]", value="0")
+
+ # Bit adcess not valid for a reference.
self.expect(
"frame var 'idx_1_ref[0]'",
error=True,
- substrs=["subscripted value is not an array or pointer"],
+ substrs=["bitfield range 0-0 is not valid"],
)
+
+ # Base should be a "pointer to T" and index should be of an integral type.
self.expect(
"frame var 'int_arr[int_ptr]'",
error=True,
@@ -105,6 +106,8 @@
)
self.runCmd("settings set target.experimental.use-DIL true")
+ self.runCmd("script from myArraySynthProvider import *")
+ self.runCmd("type synth add -l myArraySynthProvider myArray")
# Test synthetic value subscription
self.expect_var_path("vector[1]", value="2")
@@ -113,3 +116,7 @@
error=True,
substrs=["array index 100 is not valid"],
)
+ self.expect(
+ "frame var 'ma_ptr[0]'",
+ substrs=["(myArray) ma_ptr[0] = ([0] = 7, [1] = 8, [2] = 9, [3] = 10)"],
+ )
diff --git a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/main.cpp b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/main.cpp
index a9a3612..03ad3e8 100644
--- a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/main.cpp
+++ b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/main.cpp
@@ -1,5 +1,11 @@
#include <vector>
+class myArray {
+public:
+ int m_array[4] = {7, 8, 9, 10};
+ int m_arr_size = 4;
+};
+
int main(int argc, char **argv) {
int int_arr[] = {1, 2, 3};
int *int_ptr = int_arr;
@@ -29,5 +35,8 @@
std::vector<int> vector = {1, 2, 3};
+ myArray ma;
+ myArray *ma_ptr = &ma;
+
return 0; // Set a breakpoint here
}
diff --git a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/myArraySynthProvider.py b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/myArraySynthProvider.py
new file mode 100644
index 0000000..167899b
--- /dev/null
+++ b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/myArraySynthProvider.py
@@ -0,0 +1,33 @@
+import lldb
+
+
+class myArraySynthProvider:
+ def __init__(self, valobj, dict):
+ self.valobj = valobj
+
+ def num_children(self):
+ size_valobj = self.valobj.GetChildMemberWithName("m_arr_size")
+ if size_valobj:
+ return size_valobj.GetValueAsUnsigned(0)
+ return 0
+
+ def get_child_at_index(self, index):
+ size_valobj = self.valobj.GetChildMemberWithName("m_arr_size")
+ arr = self.valobj.GetChildMemberWithName("m_array")
+ if not size_valobj or not arr:
+ return None
+ max_idx = size_valobj.GetValueAsUnsigned(0)
+ if index >= max_idx:
+ return None
+ return arr.GetChildAtIndex(index)
+
+ def get_child_index(self, name):
+ if name == "[0]":
+ return 0
+ if name == "[1]":
+ return
+ if name == "[2]":
+ return 2
+ if name == "[3]":
+ return 3
+ return -1
