Mark DWARF lines in non-debuggable methods as "not a statement".
This is a hint to the debugger that breakpoints and stepping
might not function as intended (since we have limited information).
Change-Id: I23c4a816182cc7548fcd69fbd00112225e7b1710
diff --git a/compiler/debug/dwarf/debug_line_opcode_writer.h b/compiler/debug/dwarf/debug_line_opcode_writer.h
index 58502a3..b4a4d63 100644
--- a/compiler/debug/dwarf/debug_line_opcode_writer.h
+++ b/compiler/debug/dwarf/debug_line_opcode_writer.h
@@ -36,7 +36,7 @@
public:
static constexpr int kOpcodeBase = 13;
- static constexpr bool kDefaultIsStmt = true;
+ static constexpr bool kDefaultIsStmt = false;
static constexpr int kLineBase = -5;
static constexpr int kLineRange = 14;
@@ -81,8 +81,11 @@
this->PushUleb128(column);
}
- void NegateStmt() {
- this->PushUint8(DW_LNS_negate_stmt);
+ void SetIsStmt(bool is_stmt) {
+ if (is_stmt_ != is_stmt) {
+ this->PushUint8(DW_LNS_negate_stmt);
+ is_stmt_ = is_stmt;
+ }
}
void SetBasicBlock() {
@@ -112,6 +115,7 @@
current_address_ = 0;
current_file_ = 1;
current_line_ = 1;
+ is_stmt_ = kDefaultIsStmt;
}
// Uncoditionally set address using the long encoding.
@@ -227,7 +231,8 @@
code_factor_bits_(codeFactorBits),
current_address_(0),
current_file_(1),
- current_line_(1) {
+ current_line_(1),
+ is_stmt_(kDefaultIsStmt) {
}
private:
@@ -244,6 +249,7 @@
uint64_t current_address_;
int current_file_;
int current_line_;
+ bool is_stmt_;
std::vector<uintptr_t> patch_locations_;
DISALLOW_COPY_AND_ASSIGN(DebugLineOpCodeWriter);
diff --git a/compiler/debug/dwarf/dwarf_test.cc b/compiler/debug/dwarf/dwarf_test.cc
index e455d0d..2ba3af5 100644
--- a/compiler/debug/dwarf/dwarf_test.cc
+++ b/compiler/debug/dwarf/dwarf_test.cc
@@ -217,7 +217,9 @@
DW_CHECK_NEXT("Advance Line by 2 to 3");
opcodes.SetColumn(4);
DW_CHECK_NEXT("Set column to 4");
- opcodes.NegateStmt();
+ opcodes.SetIsStmt(true);
+ DW_CHECK_NEXT("Set is_stmt to 1");
+ opcodes.SetIsStmt(false);
DW_CHECK_NEXT("Set is_stmt to 0");
opcodes.SetBasicBlock();
DW_CHECK_NEXT("Set basic block");
diff --git a/compiler/debug/elf_debug_line_writer.h b/compiler/debug/elf_debug_line_writer.h
index d3859ca..11be4e9 100644
--- a/compiler/debug/elf_debug_line_writer.h
+++ b/compiler/debug/elf_debug_line_writer.h
@@ -184,6 +184,10 @@
// Generate mapping opcodes from PC to Java lines.
if (file_index != 0) {
+ // If the method was not compiled as native-debuggable, we still generate all available
+ // lines, but we try to prevent the debugger from stepping and setting breakpoints since
+ // the information is too inaccurate for that (breakpoints would be set after the calls).
+ const bool default_is_stmt = mi->is_native_debuggable;
bool first = true;
for (SrcMapElem pc2dex : pc2dex_map) {
uint32_t pc = pc2dex.from_;
@@ -205,13 +209,14 @@
// Assume that any preceding code is prologue.
int first_line = dex2line_map.front().line_;
// Prologue is not a sensible place for a breakpoint.
- opcodes.NegateStmt();
+ opcodes.SetIsStmt(false);
opcodes.AddRow(method_address, first_line);
- opcodes.NegateStmt();
opcodes.SetPrologueEnd();
}
+ opcodes.SetIsStmt(default_is_stmt);
opcodes.AddRow(method_address + pc, line);
} else if (line != opcodes.CurrentLine()) {
+ opcodes.SetIsStmt(default_is_stmt);
opcodes.AddRow(method_address + pc, line);
}
}
diff --git a/compiler/debug/method_debug_info.h b/compiler/debug/method_debug_info.h
index 6b3dd8c..bb09f7e 100644
--- a/compiler/debug/method_debug_info.h
+++ b/compiler/debug/method_debug_info.h
@@ -30,6 +30,7 @@
uint32_t access_flags;
const DexFile::CodeItem* code_item;
bool deduped;
+ bool is_native_debuggable;
uintptr_t low_pc;
uintptr_t high_pc;
CompiledMethod* compiled_method;