Move sp/pc not changing check into Unwinder.
Remove this check from the DwarfSection class.
Rather than have every step function make the check, doing it at the
top level avoids having every function do the same check.
Bug: 68167269
Test: New unit tests, ran debuggerd -b on processes.
Change-Id: I23b7c799faaf26c93c1b72848df18c78de6c42fb
diff --git a/libunwindstack/DwarfSection.cpp b/libunwindstack/DwarfSection.cpp
index b8164c5..2292168 100644
--- a/libunwindstack/DwarfSection.cpp
+++ b/libunwindstack/DwarfSection.cpp
@@ -107,7 +107,6 @@
return false;
}
- AddressType prev_pc = regs->pc();
AddressType prev_cfa = regs->sp();
AddressType cfa;
@@ -233,8 +232,8 @@
*finished = (cur_regs->pc() == 0) ? true : false;
cur_regs->set_sp(cfa);
- // Return false if the unwind is not finished or the cfa and pc didn't change.
- return *finished || prev_cfa != cfa || prev_pc != cur_regs->pc();
+
+ return true;
}
template <typename AddressType>
diff --git a/libunwindstack/Unwinder.cpp b/libunwindstack/Unwinder.cpp
index 2190711..2e46a11 100644
--- a/libunwindstack/Unwinder.cpp
+++ b/libunwindstack/Unwinder.cpp
@@ -87,8 +87,10 @@
bool return_address_attempt = false;
bool adjust_pc = false;
for (; frames_.size() < max_frames_;) {
- MapInfo* map_info = maps_->Find(regs_->pc());
+ uint64_t cur_pc = regs_->pc();
+ uint64_t cur_sp = regs_->sp();
+ MapInfo* map_info = maps_->Find(regs_->pc());
uint64_t rel_pc;
Elf* elf;
if (map_info == nullptr) {
@@ -138,6 +140,7 @@
}
}
}
+
if (!stepped) {
if (return_address_attempt) {
// Remove the speculative frame.
@@ -157,6 +160,11 @@
} else {
return_address_attempt = false;
}
+
+ // If the pc and sp didn't change, then consider everything stopped.
+ if (cur_pc == regs_->pc() && cur_sp == regs_->sp()) {
+ break;
+ }
}
}
diff --git a/libunwindstack/tests/DwarfSectionImplTest.cpp b/libunwindstack/tests/DwarfSectionImplTest.cpp
index 7e85bbb..5b9f3ee 100644
--- a/libunwindstack/tests/DwarfSectionImplTest.cpp
+++ b/libunwindstack/tests/DwarfSectionImplTest.cpp
@@ -431,22 +431,6 @@
EXPECT_EQ(0x80000000U, regs.pc());
}
-TYPED_TEST_P(DwarfSectionImplTest, Eval_same_cfa_same_pc) {
- DwarfCie cie{.version = 3, .return_address_register = 5};
- RegsImplFake<TypeParam> regs(10, 9);
- dwarf_loc_regs_t loc_regs;
-
- regs.set_pc(0x100);
- regs.set_sp(0x2000);
- regs[5] = 0x100;
- regs[8] = 0x2000;
- loc_regs[CFA_REG] = DwarfLocation{DWARF_LOCATION_REGISTER, {8, 0}};
- bool finished;
- ASSERT_FALSE(this->section_->Eval(&cie, &this->memory_, loc_regs, ®s, &finished));
- EXPECT_EQ(0x2000U, regs.sp());
- EXPECT_EQ(0x100U, regs.pc());
-}
-
TYPED_TEST_P(DwarfSectionImplTest, GetCie_fail_should_not_cache) {
ASSERT_TRUE(this->section_->GetCie(0x4000) == nullptr);
EXPECT_EQ(DWARF_ERROR_MEMORY_INVALID, this->section_->last_error());
@@ -872,9 +856,9 @@
Eval_cfa_bad, Eval_cfa_register_prev, Eval_cfa_register_from_value, Eval_double_indirection,
Eval_invalid_register, Eval_different_reg_locations, Eval_return_address_undefined,
Eval_pc_zero, Eval_return_address, Eval_ignore_large_reg_loc, Eval_reg_expr, Eval_reg_val_expr,
- Eval_same_cfa_same_pc, GetCie_fail_should_not_cache, GetCie_32_version_check,
- GetCie_negative_data_alignment_factor, GetCie_64_no_augment, GetCie_augment, GetCie_version_3,
- GetCie_version_4, GetFdeFromOffset_fail_should_not_cache, GetFdeFromOffset_32_no_augment,
+ GetCie_fail_should_not_cache, GetCie_32_version_check, GetCie_negative_data_alignment_factor,
+ GetCie_64_no_augment, GetCie_augment, GetCie_version_3, GetCie_version_4,
+ GetFdeFromOffset_fail_should_not_cache, GetFdeFromOffset_32_no_augment,
GetFdeFromOffset_32_no_augment_non_zero_segment_size, GetFdeFromOffset_32_augment,
GetFdeFromOffset_64_no_augment, GetFdeFromOffset_cached, GetCfaLocationInfo_cie_not_cached,
GetCfaLocationInfo_cie_cached, Log);
diff --git a/libunwindstack/tests/UnwinderTest.cpp b/libunwindstack/tests/UnwinderTest.cpp
index 8a90bae..869d118 100644
--- a/libunwindstack/tests/UnwinderTest.cpp
+++ b/libunwindstack/tests/UnwinderTest.cpp
@@ -127,6 +127,7 @@
void SetUp() override {
ElfInterfaceFake::FakeClear();
regs_.FakeSetMachineType(EM_ARM);
+ regs_.FakeSetReturnAddressValid(false);
}
static MapsFake maps_;
@@ -610,6 +611,71 @@
EXPECT_EQ(PROT_READ | PROT_WRITE, frame->map_flags);
}
+// Verify that an unwind stops when the sp and pc don't change.
+TEST_F(UnwinderTest, sp_pc_do_not_change) {
+ ElfInterfaceFake::FakePushFunctionData(FunctionData("Frame0", 0));
+ ElfInterfaceFake::FakePushFunctionData(FunctionData("Frame1", 1));
+ ElfInterfaceFake::FakePushFunctionData(FunctionData("Frame2", 2));
+ ElfInterfaceFake::FakePushFunctionData(FunctionData("Frame3", 3));
+ ElfInterfaceFake::FakePushFunctionData(FunctionData("Frame4", 4));
+
+ regs_.FakeSetPc(0x1000);
+ regs_.FakeSetSp(0x10000);
+ ElfInterfaceFake::FakePushStepData(StepData(0x33402, 0x10010, false));
+ ElfInterfaceFake::FakePushStepData(StepData(0x33502, 0x10020, false));
+ ElfInterfaceFake::FakePushStepData(StepData(0x33502, 0x10020, false));
+ ElfInterfaceFake::FakePushStepData(StepData(0x33502, 0x10020, false));
+ ElfInterfaceFake::FakePushStepData(StepData(0x33502, 0x10020, false));
+ ElfInterfaceFake::FakePushStepData(StepData(0, 0, true));
+
+ Unwinder unwinder(64, &maps_, ®s_, process_memory_);
+ unwinder.Unwind();
+
+ ASSERT_EQ(3U, unwinder.NumFrames());
+
+ auto* frame = &unwinder.frames()[0];
+ EXPECT_EQ(0U, frame->num);
+ EXPECT_EQ(0U, frame->rel_pc);
+ EXPECT_EQ(0x1000U, frame->pc);
+ EXPECT_EQ(0x10000U, frame->sp);
+ EXPECT_EQ("Frame0", frame->function_name);
+ EXPECT_EQ(0U, frame->function_offset);
+ EXPECT_EQ("/system/fake/libc.so", frame->map_name);
+ EXPECT_EQ(0U, frame->map_offset);
+ EXPECT_EQ(0x1000U, frame->map_start);
+ EXPECT_EQ(0x8000U, frame->map_end);
+ EXPECT_EQ(0U, frame->map_load_bias);
+ EXPECT_EQ(PROT_READ | PROT_WRITE, frame->map_flags);
+
+ frame = &unwinder.frames()[1];
+ EXPECT_EQ(1U, frame->num);
+ EXPECT_EQ(0x400U, frame->rel_pc);
+ EXPECT_EQ(0x33400U, frame->pc);
+ EXPECT_EQ(0x10010U, frame->sp);
+ EXPECT_EQ("Frame1", frame->function_name);
+ EXPECT_EQ(1U, frame->function_offset);
+ EXPECT_EQ("/fake/compressed.so", frame->map_name);
+ EXPECT_EQ(0U, frame->map_offset);
+ EXPECT_EQ(0x33000U, frame->map_start);
+ EXPECT_EQ(0x34000U, frame->map_end);
+ EXPECT_EQ(0U, frame->map_load_bias);
+ EXPECT_EQ(PROT_READ | PROT_WRITE, frame->map_flags);
+
+ frame = &unwinder.frames()[2];
+ EXPECT_EQ(2U, frame->num);
+ EXPECT_EQ(0x500U, frame->rel_pc);
+ EXPECT_EQ(0x33500U, frame->pc);
+ EXPECT_EQ(0x10020U, frame->sp);
+ EXPECT_EQ("Frame2", frame->function_name);
+ EXPECT_EQ(2U, frame->function_offset);
+ EXPECT_EQ("/fake/compressed.so", frame->map_name);
+ EXPECT_EQ(0U, frame->map_offset);
+ EXPECT_EQ(0x33000U, frame->map_start);
+ EXPECT_EQ(0x34000U, frame->map_end);
+ EXPECT_EQ(0U, frame->map_load_bias);
+ EXPECT_EQ(PROT_READ | PROT_WRITE, frame->map_flags);
+}
+
// Verify format frame code.
TEST_F(UnwinderTest, format_frame_static) {
FrameData frame;