Implement CFI for JNI.
CFI is necessary for stack unwinding in gdb, lldb, and libunwind.
Change-Id: I37eb7973f99a6975034cf0e699e138c3a9aba10f
diff --git a/compiler/utils/arm/assembler_arm.cc b/compiler/utils/arm/assembler_arm.cc
index 8059289..c410660 100644
--- a/compiler/utils/arm/assembler_arm.cc
+++ b/compiler/utils/arm/assembler_arm.cc
@@ -370,40 +370,46 @@
}
}
+static dwarf::Reg DWARFReg(Register reg) {
+ return dwarf::Reg::ArmCore(static_cast<int>(reg));
+}
+
+static dwarf::Reg DWARFReg(SRegister reg) {
+ return dwarf::Reg::ArmFp(static_cast<int>(reg));
+}
+
constexpr size_t kFramePointerSize = 4;
void ArmAssembler::BuildFrame(size_t frame_size, ManagedRegister method_reg,
const std::vector<ManagedRegister>& callee_save_regs,
const ManagedRegisterEntrySpills& entry_spills) {
+ CHECK_EQ(buffer_.Size(), 0U); // Nothing emitted yet
CHECK_ALIGNED(frame_size, kStackAlignment);
CHECK_EQ(R0, method_reg.AsArm().AsCoreRegister());
// Push callee saves and link register.
- RegList push_list = 1 << LR;
- size_t pushed_values = 1;
- int32_t min_s = kNumberOfSRegisters;
- int32_t max_s = -1;
- for (size_t i = 0; i < callee_save_regs.size(); i++) {
- if (callee_save_regs.at(i).AsArm().IsCoreRegister()) {
- Register reg = callee_save_regs.at(i).AsArm().AsCoreRegister();
- push_list |= 1 << reg;
- pushed_values++;
+ RegList core_spill_mask = 1 << LR;
+ uint32_t fp_spill_mask = 0;
+ for (const ManagedRegister& reg : callee_save_regs) {
+ if (reg.AsArm().IsCoreRegister()) {
+ core_spill_mask |= 1 << reg.AsArm().AsCoreRegister();
} else {
- CHECK(callee_save_regs.at(i).AsArm().IsSRegister());
- min_s = std::min(static_cast<int>(callee_save_regs.at(i).AsArm().AsSRegister()), min_s);
- max_s = std::max(static_cast<int>(callee_save_regs.at(i).AsArm().AsSRegister()), max_s);
+ fp_spill_mask |= 1 << reg.AsArm().AsSRegister();
}
}
- PushList(push_list);
- if (max_s != -1) {
- pushed_values += 1 + max_s - min_s;
- vpushs(static_cast<SRegister>(min_s), 1 + max_s - min_s);
+ PushList(core_spill_mask);
+ cfi_.AdjustCFAOffset(POPCOUNT(core_spill_mask) * kFramePointerSize);
+ cfi_.RelOffsetForMany(DWARFReg(Register(0)), 0, core_spill_mask, kFramePointerSize);
+ if (fp_spill_mask != 0) {
+ vpushs(SRegister(CTZ(fp_spill_mask)), POPCOUNT(fp_spill_mask));
+ cfi_.AdjustCFAOffset(POPCOUNT(fp_spill_mask) * kFramePointerSize);
+ cfi_.RelOffsetForMany(DWARFReg(SRegister(0)), 0, fp_spill_mask, kFramePointerSize);
}
// Increase frame to required size.
+ int pushed_values = POPCOUNT(core_spill_mask) + POPCOUNT(fp_spill_mask);
CHECK_GT(frame_size, pushed_values * kFramePointerSize); // Must at least have space for Method*.
- size_t adjust = frame_size - (pushed_values * kFramePointerSize);
- IncreaseFrameSize(adjust);
+ IncreaseFrameSize(frame_size - pushed_values * kFramePointerSize); // handles CFI as well.
// Write out Method*.
StoreToOffset(kStoreWord, R0, SP, 0);
@@ -432,46 +438,46 @@
void ArmAssembler::RemoveFrame(size_t frame_size,
const std::vector<ManagedRegister>& callee_save_regs) {
CHECK_ALIGNED(frame_size, kStackAlignment);
+ cfi_.RememberState();
+
// Compute callee saves to pop and PC.
- RegList pop_list = 1 << PC;
- size_t pop_values = 1;
- int32_t min_s = kNumberOfSRegisters;
- int32_t max_s = -1;
- for (size_t i = 0; i < callee_save_regs.size(); i++) {
- if (callee_save_regs.at(i).AsArm().IsCoreRegister()) {
- Register reg = callee_save_regs.at(i).AsArm().AsCoreRegister();
- pop_list |= 1 << reg;
- pop_values++;
+ RegList core_spill_mask = 1 << PC;
+ uint32_t fp_spill_mask = 0;
+ for (const ManagedRegister& reg : callee_save_regs) {
+ if (reg.AsArm().IsCoreRegister()) {
+ core_spill_mask |= 1 << reg.AsArm().AsCoreRegister();
} else {
- CHECK(callee_save_regs.at(i).AsArm().IsSRegister());
- min_s = std::min(static_cast<int>(callee_save_regs.at(i).AsArm().AsSRegister()), min_s);
- max_s = std::max(static_cast<int>(callee_save_regs.at(i).AsArm().AsSRegister()), max_s);
+ fp_spill_mask |= 1 << reg.AsArm().AsSRegister();
}
}
- if (max_s != -1) {
- pop_values += 1 + max_s - min_s;
- }
-
// Decrease frame to start of callee saves.
+ int pop_values = POPCOUNT(core_spill_mask) + POPCOUNT(fp_spill_mask);
CHECK_GT(frame_size, pop_values * kFramePointerSize);
- size_t adjust = frame_size - (pop_values * kFramePointerSize);
- DecreaseFrameSize(adjust);
+ DecreaseFrameSize(frame_size - (pop_values * kFramePointerSize)); // handles CFI as well.
- if (max_s != -1) {
- vpops(static_cast<SRegister>(min_s), 1 + max_s - min_s);
+ if (fp_spill_mask != 0) {
+ vpops(SRegister(CTZ(fp_spill_mask)), POPCOUNT(fp_spill_mask));
+ cfi_.AdjustCFAOffset(-kFramePointerSize * POPCOUNT(fp_spill_mask));
+ cfi_.RestoreMany(DWARFReg(SRegister(0)), fp_spill_mask);
}
// Pop callee saves and PC.
- PopList(pop_list);
+ PopList(core_spill_mask);
+
+ // The CFI should be restored for any code that follows the exit block.
+ cfi_.RestoreState();
+ cfi_.DefCFAOffset(frame_size);
}
void ArmAssembler::IncreaseFrameSize(size_t adjust) {
AddConstant(SP, -adjust);
+ cfi_.AdjustCFAOffset(adjust);
}
void ArmAssembler::DecreaseFrameSize(size_t adjust) {
AddConstant(SP, adjust);
+ cfi_.AdjustCFAOffset(-adjust);
}
void ArmAssembler::Store(FrameOffset dest, ManagedRegister msrc, size_t size) {