Spill possibly reference holding registers for runtime calls.
Live references may be in registers when we crawl a stack for GC during
a runtime call. Whilst an exception won't occur we need to save the
callee save registers into the frame so the stack crawl can find their
values. Create variants of the callee save method to save just the
registers that are necessary.
Change-Id: I6fa479bffcbc333fe846f9bd3ef2e626e0209ed9
diff --git a/src/stub_arm.cc b/src/stub_arm.cc
index aeee8c8..bb36415 100644
--- a/src/stub_arm.cc
+++ b/src/stub_arm.cc
@@ -11,8 +11,6 @@
ByteArray* ArmCreateResolutionTrampoline(Runtime::TrampolineType type) {
UniquePtr<ArmAssembler> assembler( static_cast<ArmAssembler*>(Assembler::Create(kArm)) );
- RegList save = (1 << R0) | (1 << R1) | (1 << R2) | (1 << R3) | (1 << LR);
-
// | Out args |
// | Method* | <- SP on entry
// | LR | return address into caller
@@ -20,6 +18,7 @@
// | R2 | possible argument
// | R1 | possible argument
// | R0 | method index (loaded from code and method array - will be converted to Method*)
+ RegList save = (1 << R0) | (1 << R1) | (1 << R2) | (1 << R3) | (1 << LR);
__ PushList(save);
__ mov(R1, ShifterOperand(SP)); // Pass address of saved R0... in R1
__ LoadFromOffset(kLoadWord, R12, TR,
@@ -29,13 +28,11 @@
__ IncreaseFrameSize(12); // 3 words of space for alignment
// Call to unresolved direct method trampoline (method_idx, sp, Thread*, is_static)
__ blx(R12);
- // Save code address returned into R12
- __ mov(R12, ShifterOperand(R0));
+ __ mov(R12, ShifterOperand(R0)); // Save code address returned into R12
// Restore registers which may have been modified by GC and R0 which will now hold the method*
__ DecreaseFrameSize(12);
__ PopList(save);
- // Leaf call to method's code
- __ mov(PC, ShifterOperand(R12));
+ __ mov(PC, ShifterOperand(R12)); // Leaf call to method's code
__ bkpt(0);
@@ -53,21 +50,19 @@
ByteArray* CreateAbstractMethodErrorStub() {
UniquePtr<ArmAssembler> assembler( static_cast<ArmAssembler*>(Assembler::Create(kArm)) );
-
// Save callee saves and ready frame for exception delivery
- RegList save = (1 << R1) | (1 << R2) | (1 << R3) | (1 << R4) | (1 << R5) | (1 << R6) | (1 << R7) |
- (1 << R8) | (1 << R9) | (1 << R10) | (1 << R11) | (1 << LR);
- __ PushList(save);
- __ Emit(0xed2d0a20); // vpush {s0-s31}
- __ IncreaseFrameSize(16); // 4 words of space, bottom word will hold callee save Method*
+ RegList save = (1 << R4) | (1 << R5) | (1 << R6) | (1 << R7) | (1 << R8) | (1 << R9) |
+ (1 << R10) | (1 << R11) | (1 << LR);
+ __ PushList(save); // push {r4-r11, lr} - 9 words of callee saves
+ __ Emit(0xed2d0a20); // vpush {s0-s31}
+ __ IncreaseFrameSize(12); // 3 words of space, bottom word will hold callee save Method*
// R0 is the Method* already
__ mov(R1, ShifterOperand(R9)); // Pass Thread::Current() in R1
__ mov(R2, ShifterOperand(SP)); // Pass SP in R2
// Call to throw AbstractMethodError
__ LoadFromOffset(kLoadWord, R12, TR, OFFSETOF_MEMBER(Thread, pThrowAbstractMethodErrorFromCode));
- // Leaf call to routine that never returns
- __ mov(PC, ShifterOperand(R12));
+ __ mov(PC, ShifterOperand(R12)); // Leaf call to routine that never returns
__ bkpt(0);
@@ -85,35 +80,20 @@
ByteArray* CreateJniStub() {
UniquePtr<ArmAssembler> assembler( static_cast<ArmAssembler*>(Assembler::Create(kArm)) );
-
+ // Build frame and save argument registers and LR.
RegList save = (1 << R0) | (1 << R1) | (1 << R2) | (1 << R3) | (1 << LR);
-
- // Build frame and save registers. Save 5 registers.
__ PushList(save);
- // Ensure 16-byte alignment
- __ AddConstant(SP, -12);
-
- // Pass Thread::Current() in R0
- __ mov(R0, ShifterOperand(R9));
-
+ __ AddConstant(SP, -12); // Ensure 16-byte alignment
+ __ mov(R0, ShifterOperand(R9)); // Pass Thread::Current() in R0
// Call FindNativeMethod
__ LoadFromOffset(kLoadWord, R12, TR, OFFSETOF_MEMBER(Thread, pFindNativeMethod));
__ blx(R12);
-
- // Save result of FindNativeMethod in R12
- __ mov(R12, ShifterOperand(R0));
-
- // Restore registers (including outgoing arguments)
- __ AddConstant(SP, 12);
+ __ mov(R12, ShifterOperand(R0)); // Save result of FindNativeMethod in R12
+ __ AddConstant(SP, 12); // Restore registers (including outgoing arguments)
__ PopList(save);
-
__ cmp(R12, ShifterOperand(0));
-
- // If R12 != 0 tail call into native code
- __ mov(PC, ShifterOperand(R12), NE);
-
- // Return to caller to handle exception
- __ mov(PC, ShifterOperand(LR));
+ __ mov(PC, ShifterOperand(R12), NE); // If R12 != 0 tail call into native code
+ __ mov(PC, ShifterOperand(LR)); // Return to caller to handle exception
assembler->EmitSlowPaths();