jwnhy created this revision.
jwnhy added a reviewer: JDevlieghere.
Herald added a project: All.
jwnhy requested review of this revision.
Herald added a project: LLDB.
Herald added a subscriber: lldb-commits.
This patch resolves an issue where a value is incorrectly displayed
if it is represented by DW_OP_deref and DW_OP_lt combined.
This issue is caused by lldb treating DW_OP_deref generic types
as unsigned by default, while DW_OP_lt should perform signed
comparison with these generic types by DWARF v5 standard.
This patch resolves this issue by making everything loaded by
DW_OP_deref as signed. As lldb does not really support generic
type, this is probably the best we can do.
A small regression test is also included in this patch.
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D147425
Files:
lldb/source/Expression/DWARFExpression.cpp
lldb/test/API/commands/expression/signed-dw-op-deref/Makefile
lldb/test/API/commands/expression/signed-dw-op-deref/TestSignedDeref.py
lldb/test/API/commands/expression/signed-dw-op-deref/main.c
Index: lldb/test/API/commands/expression/signed-dw-op-deref/main.c
===================================================================
--- /dev/null
+++ lldb/test/API/commands/expression/signed-dw-op-deref/main.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+int a;
+signed char b = -48;
+static int func_12(int p_13) {
+ for (;a;); // break here
+ return 0;
+}
+int main() {
+ func_12(0 > b);
+ printf(0);
+ return 0;
+}
Index: lldb/test/API/commands/expression/signed-dw-op-deref/TestSignedDeref.py
===================================================================
--- /dev/null
+++ lldb/test/API/commands/expression/signed-dw-op-deref/TestSignedDeref.py
@@ -0,0 +1,11 @@
+"""Test that we can print values represented via DW_OP_deref and DW_OP_lt"""
+
+import lldb
+from lldbsuite.test.lldbtest import *
+
+class SignedDerefTestCase(TestBase):
+ def test_signed_div(self):
+ """Test that we can print values represented via DW_OP_deref and
DW_OP_lt"""
+ self.build()
+ _, process, _, bkpt = lldbutil.run_to_source_breakpoint(self, '//
break here', lldb.SBFileSpec('main.c'))
+ self.expect_expr('p_13', result_type='int', result_value='1')
Index: lldb/test/API/commands/expression/signed-dw-op-deref/Makefile
===================================================================
--- /dev/null
+++ lldb/test/API/commands/expression/signed-dw-op-deref/Makefile
@@ -0,0 +1,5 @@
+C_SOURCES := main.c
+CFLAGS_EXTRAS := -g -O1
+override CC := gcc
+
+include Makefile.rules
Index: lldb/source/Expression/DWARFExpression.cpp
===================================================================
--- lldb/source/Expression/DWARFExpression.cpp
+++ lldb/source/Expression/DWARFExpression.cpp
@@ -1030,6 +1030,7 @@
if (ABISP abi_sp = process->GetABI())
pointer_value = abi_sp->FixCodeAddress(pointer_value);
stack.back().GetScalar() = pointer_value;
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
} else {
if (error_ptr)
@@ -1120,6 +1121,7 @@
break;
}
stack.back().GetScalar() = ptr;
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
} break;
case Value::ValueType::FileAddress: {
@@ -1147,6 +1149,7 @@
stack.back().GetScalar() = DerefSizeExtractDataHelper(
addr_bytes, size, objfile->GetByteOrder(), size);
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
break;
} else {
@@ -1177,6 +1180,7 @@
stack.back().GetScalar() =
DerefSizeExtractDataHelper(addr_bytes, sizeof(addr_bytes),
process->GetByteOrder(), size);
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
} else {
if (error_ptr)
Index: lldb/test/API/commands/expression/signed-dw-op-deref/main.c
===================================================================
--- /dev/null
+++ lldb/test/API/commands/expression/signed-dw-op-deref/main.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+int a;
+signed char b = -48;
+static int func_12(int p_13) {
+ for (;a;); // break here
+ return 0;
+}
+int main() {
+ func_12(0 > b);
+ printf(0);
+ return 0;
+}
Index: lldb/test/API/commands/expression/signed-dw-op-deref/TestSignedDeref.py
===================================================================
--- /dev/null
+++ lldb/test/API/commands/expression/signed-dw-op-deref/TestSignedDeref.py
@@ -0,0 +1,11 @@
+"""Test that we can print values represented via DW_OP_deref and DW_OP_lt"""
+
+import lldb
+from lldbsuite.test.lldbtest import *
+
+class SignedDerefTestCase(TestBase):
+ def test_signed_div(self):
+ """Test that we can print values represented via DW_OP_deref and DW_OP_lt"""
+ self.build()
+ _, process, _, bkpt = lldbutil.run_to_source_breakpoint(self, '// break here', lldb.SBFileSpec('main.c'))
+ self.expect_expr('p_13', result_type='int', result_value='1')
Index: lldb/test/API/commands/expression/signed-dw-op-deref/Makefile
===================================================================
--- /dev/null
+++ lldb/test/API/commands/expression/signed-dw-op-deref/Makefile
@@ -0,0 +1,5 @@
+C_SOURCES := main.c
+CFLAGS_EXTRAS := -g -O1
+override CC := gcc
+
+include Makefile.rules
Index: lldb/source/Expression/DWARFExpression.cpp
===================================================================
--- lldb/source/Expression/DWARFExpression.cpp
+++ lldb/source/Expression/DWARFExpression.cpp
@@ -1030,6 +1030,7 @@
if (ABISP abi_sp = process->GetABI())
pointer_value = abi_sp->FixCodeAddress(pointer_value);
stack.back().GetScalar() = pointer_value;
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
} else {
if (error_ptr)
@@ -1120,6 +1121,7 @@
break;
}
stack.back().GetScalar() = ptr;
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
} break;
case Value::ValueType::FileAddress: {
@@ -1147,6 +1149,7 @@
stack.back().GetScalar() = DerefSizeExtractDataHelper(
addr_bytes, size, objfile->GetByteOrder(), size);
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
break;
} else {
@@ -1177,6 +1180,7 @@
stack.back().GetScalar() =
DerefSizeExtractDataHelper(addr_bytes, sizeof(addr_bytes),
process->GetByteOrder(), size);
+ stack.back().GetScalar().MakeSigned();
stack.back().ClearContext();
} else {
if (error_ptr)
_______________________________________________
lldb-commits mailing list
lldb-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
