Rewrite DwarfSectionImpl::InsertFde
Simplify and fix the algorithm.
For consecutive functions (eg [10,20] [20,30]) without
padding in between, the old algorithm would drop FDEs.
Bug: http://b/150050915
Test: libunwindstack_test
Change-Id: Ie886922bec262fb64d4b2ecf01c2961d0652dcdb
(cherry picked from commit a6617cb17926a9868a900ce43c9b358bafe88d9b)
diff --git a/libunwindstack/DwarfSection.cpp b/libunwindstack/DwarfSection.cpp
index e6263f8..18bd490 100644
--- a/libunwindstack/DwarfSection.cpp
+++ b/libunwindstack/DwarfSection.cpp
@@ -621,29 +621,9 @@
uint64_t start = fde->pc_start;
uint64_t end = fde->pc_end;
auto it = fdes_.upper_bound(start);
- bool add_element = false;
- while (it != fdes_.end() && start < end) {
- if (add_element) {
- add_element = false;
- if (end < it->second.first) {
- if (it->first == end) {
- return;
- }
- fdes_[end] = std::make_pair(start, fde);
- return;
- }
- if (start != it->second.first) {
- fdes_[it->second.first] = std::make_pair(start, fde);
- }
- }
- if (start < it->first) {
- if (end < it->second.first) {
- if (it->first != end) {
- fdes_[end] = std::make_pair(start, fde);
- }
- return;
- }
- add_element = true;
+ while (it != fdes_.end() && start < end && it->second.first < end) {
+ if (start < it->second.first) {
+ fdes_[it->second.first] = std::make_pair(start, fde);
}
start = it->first;
++it;
diff --git a/libunwindstack/tests/DwarfDebugFrameTest.cpp b/libunwindstack/tests/DwarfDebugFrameTest.cpp
index b6f574a..fac8a0e 100644
--- a/libunwindstack/tests/DwarfDebugFrameTest.cpp
+++ b/libunwindstack/tests/DwarfDebugFrameTest.cpp
@@ -754,16 +754,24 @@
SetFde32(&this->memory_, 0x5400, 0xfc, 0, 0xa00, 0x100);
// FDE 4 (0x100 - 0xb00)
SetFde32(&this->memory_, 0x5500, 0xfc, 0, 0x150, 0xa00);
- // FDE 5 (0x0 - 0x50)
- SetFde32(&this->memory_, 0x5600, 0xfc, 0, 0, 0x50);
+ // FDE 5 (0x50 - 0xa0)
+ SetFde32(&this->memory_, 0x5600, 0xfc, 0, 0x50, 0x50);
+ // FDE 6 (0x0 - 0x50)
+ SetFde32(&this->memory_, 0x5700, 0xfc, 0, 0, 0x50);
- this->debug_frame_->Init(0x5000, 0x700, 0);
+ this->debug_frame_->Init(0x5000, 0x800, 0);
// Force reading all entries so no entries are found.
const DwarfFde* fde = this->debug_frame_->GetFdeFromPc(0xfffff);
ASSERT_TRUE(fde == nullptr);
- // 0x0 - 0x50 FDE 5
+ // 0x50 - 0xa0 FDE 5
+ fde = this->debug_frame_->GetFdeFromPc(0x60);
+ ASSERT_TRUE(fde != nullptr);
+ EXPECT_EQ(0x50U, fde->pc_start);
+ EXPECT_EQ(0xa0U, fde->pc_end);
+
+ // 0x0 - 0x50 FDE 6
fde = this->debug_frame_->GetFdeFromPc(0x10);
ASSERT_TRUE(fde != nullptr);
EXPECT_EQ(0U, fde->pc_start);
@@ -812,6 +820,56 @@
EXPECT_EQ(0xb50U, fde->pc_end);
}
+TYPED_TEST_P(DwarfDebugFrameTest, GetFdeFromPc_overlap) {
+ SetCie32(&this->memory_, 0x5000, 0xfc, std::vector<uint8_t>{1, '\0', 0, 0, 1});
+
+ // FDE 0 (0x100 - 0x200)
+ SetFde32(&this->memory_, 0x5100, 0xfc, 0, 0x100, 0x100);
+ // FDE 1 (0x50 - 0x550)
+ SetFde32(&this->memory_, 0x5200, 0xfc, 0, 0x50, 0x500);
+ // FDE 2 (0x00 - 0x800)
+ SetFde32(&this->memory_, 0x5300, 0xfc, 0, 0x0, 0x800);
+
+ this->debug_frame_->Init(0x5000, 0x400, 0);
+
+ // Force reading all entries so no entries are found.
+ const DwarfFde* fde = this->debug_frame_->GetFdeFromPc(0xfffff);
+ ASSERT_TRUE(fde == nullptr);
+
+ // 0x0 - 0x50 FDE 2
+ fde = this->debug_frame_->GetFdeFromPc(0x10);
+ ASSERT_TRUE(fde != nullptr);
+ EXPECT_EQ(0x0U, fde->pc_start);
+ EXPECT_EQ(0x800U, fde->pc_end);
+
+ // 0x50 - 0x100 FDE 1
+ fde = this->debug_frame_->GetFdeFromPc(0x60);
+ ASSERT_TRUE(fde != nullptr);
+ EXPECT_EQ(0x50U, fde->pc_start);
+ EXPECT_EQ(0x550U, fde->pc_end);
+
+ // 0x100 - 0x200 FDE 0
+ fde = this->debug_frame_->GetFdeFromPc(0x170);
+ ASSERT_TRUE(fde != nullptr);
+ EXPECT_EQ(0x100U, fde->pc_start);
+ EXPECT_EQ(0x200U, fde->pc_end);
+
+ // 0x200 - 0x550 FDE 1
+ fde = this->debug_frame_->GetFdeFromPc(0x210);
+ ASSERT_TRUE(fde != nullptr);
+ EXPECT_EQ(0x50U, fde->pc_start);
+ EXPECT_EQ(0x550U, fde->pc_end);
+
+ // 0x550 - 0x800 FDE 2
+ fde = this->debug_frame_->GetFdeFromPc(0x580);
+ ASSERT_TRUE(fde != nullptr);
+ EXPECT_EQ(0x0U, fde->pc_start);
+ EXPECT_EQ(0x800U, fde->pc_end);
+
+ fde = this->debug_frame_->GetFdeFromPc(0x810);
+ ASSERT_TRUE(fde == nullptr);
+}
+
REGISTER_TYPED_TEST_SUITE_P(
DwarfDebugFrameTest, GetFdes32, GetFdes32_after_GetFdeFromPc, GetFdes32_not_in_section,
GetFdeFromPc32, GetFdeFromPc32_reverse, GetFdeFromPc32_not_in_section, GetFdes64,
@@ -822,7 +880,7 @@
GetCieFromOffset64_version4, GetCieFromOffset32_version5, GetCieFromOffset64_version5,
GetCieFromOffset_version_invalid, GetCieFromOffset32_augment, GetCieFromOffset64_augment,
GetFdeFromOffset32_augment, GetFdeFromOffset64_augment, GetFdeFromOffset32_lsda_address,
- GetFdeFromOffset64_lsda_address, GetFdeFromPc_interleaved);
+ GetFdeFromOffset64_lsda_address, GetFdeFromPc_interleaved, GetFdeFromPc_overlap);
typedef ::testing::Types<uint32_t, uint64_t> DwarfDebugFrameTestTypes;
INSTANTIATE_TYPED_TEST_SUITE_P(Libunwindstack, DwarfDebugFrameTest, DwarfDebugFrameTestTypes);