Fix a throw returning to a frame marked for lazy deopt that captures the stacktrace.

runtime/vm/stub_code_arm.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/assembler.h"
 #include "vm/code_generator.h"
 #include "vm/cpu.h"
@@ skipping 409 matching lines @@
   COMPILE_ASSERT(PP < CODE_REG);
   COMPILE_ASSERT(CODE_REG < FP);
   COMPILE_ASSERT(FP < IP);
   __ EnterFrame((1 << PP) | (1 << CODE_REG) | (1 << FP) | (1 << IP), 0);
   __ LoadPoolPointer();
 
   // The code in this frame may not cause GC. kDeoptimizeCopyFrameRuntimeEntry
   // and kDeoptimizeFillFrameRuntimeEntry are leaf runtime calls.
   const intptr_t saved_result_slot_from_fp =
       kFirstLocalSlotFromFp + 1 - (kNumberOfCpuRegisters - R0);
+  const intptr_t saved_exception_slot_from_fp =
+      kFirstLocalSlotFromFp + 1 - (kNumberOfCpuRegisters - R0);
+  const intptr_t saved_stacktrace_slot_from_fp =
+      kFirstLocalSlotFromFp + 1 - (kNumberOfCpuRegisters - R1);
   // Result in R0 is preserved as part of pushing all registers below.
 
   // Push registers in their enumeration order: lowest register number at
   // lowest address.
   for (intptr_t i = kNumberOfCpuRegisters - 1; i >= 0; --i) {
     if (i == CODE_REG) {
       // Save the original value of CODE_REG pushed before invoking this stub
       // instead of the value used to call this stub.
       __ ldr(IP, Address(FP, kCallerSpSlotFromFp * kWordSize));
       __ Push(IP);
@@ skipping 12 matching lines @@
       __ vstmd(DB_W, SP, D16, kNumberOfDRegisters - 16);
       __ vstmd(DB_W, SP, D0, 16);
     } else {
       __ vstmd(DB_W, SP, D0, kNumberOfDRegisters);
     }
   } else {
     __ AddImmediate(SP, SP, -kNumberOfFpuRegisters * kFpuRegisterSize);
   }
 
   __ mov(R0, Operand(SP));  // Pass address of saved registers block.
-  __ mov(R1, Operand(kind == kLazyDeopt ? 1 : 0));
+  bool is_lazy = (kind == kLazyDeoptFromReturn) ||
+                 (kind == kLazyDeoptFromThrow);
+  __ mov(R1, Operand(is_lazy ? 1 : 0));
   __ ReserveAlignedFrameSpace(0);
   __ CallRuntime(kDeoptimizeCopyFrameRuntimeEntry, 2);
   // Result (R0) is stack-size (FP - SP) in bytes.
 
-  const bool preserve_result = (kind == kLazyDeopt);
-  if (preserve_result) {
+  if (kind == kLazyDeoptFromReturn) {
     // Restore result into R1 temporarily.
     __ ldr(R1, Address(FP, saved_result_slot_from_fp * kWordSize));
+  } else if (kind == kLazyDeoptFromThrow) {
+    // Restore result into R1 temporarily.
+    __ ldr(R1, Address(FP, saved_exception_slot_from_fp * kWordSize));
+    __ ldr(R2, Address(FP, saved_stacktrace_slot_from_fp * kWordSize));
   }
 
   __ RestoreCodePointer();
   __ LeaveDartFrame();
   __ sub(SP, FP, Operand(R0));
 
   // DeoptimizeFillFrame expects a Dart frame, i.e. EnterDartFrame(0), but there
   // is no need to set the correct PC marker or load PP, since they get patched.
   __ EnterStubFrame();
   __ mov(R0, Operand(FP));  // Get last FP address.
-  if (preserve_result) {
+  if (kind == kLazyDeoptFromReturn) {
     __ Push(R1);  // Preserve result as first local.
+  } else if (kind == kLazyDeoptFromThrow) {
+    __ Push(R1);  // Preserve exception as first local.
+    __ Push(R2);  // Preserve stacktrace as second local.
   }
   __ ReserveAlignedFrameSpace(0);
   __ CallRuntime(kDeoptimizeFillFrameRuntimeEntry, 1);  // Pass last FP in R0.
-  if (preserve_result) {
+  if (kind == kLazyDeoptFromReturn) {
     // Restore result into R1.
     __ ldr(R1, Address(FP, kFirstLocalSlotFromFp * kWordSize));
+  } else if (kind == kLazyDeoptFromThrow) {
+    // Restore result into R1.
+    __ ldr(R1, Address(FP, kFirstLocalSlotFromFp * kWordSize));
+    __ ldr(R2, Address(FP, (kFirstLocalSlotFromFp - 1) * kWordSize));
   }
   // Code above cannot cause GC.
   __ RestoreCodePointer();
   __ LeaveStubFrame();
 
   // Frame is fully rewritten at this point and it is safe to perform a GC.
   // Materialize any objects that were deferred by FillFrame because they
   // require allocation.
   // Enter stub frame with loading PP. The caller's PP is not materialized yet.
   __ EnterStubFrame();
-  if (preserve_result) {
+  if (kind == kLazyDeoptFromReturn) {
     __ Push(R1);  // Preserve result, it will be GC-d here.
+  } else if (kind == kLazyDeoptFromThrow) {
+    __ Push(R1);  // Preserve exception, it will be GC-d here.
+    __ Push(R2);  // Preserve stacktrace, it will be GC-d here.
   }
   __ PushObject(Smi::ZoneHandle());  // Space for the result.
   __ CallRuntime(kDeoptimizeMaterializeRuntimeEntry, 0);
   // Result tells stub how many bytes to remove from the expression stack
   // of the bottom-most frame. They were used as materialization arguments.
   __ Pop(R1);
-  if (preserve_result) {
+  if (kind == kLazyDeoptFromReturn) {
     __ Pop(R0);  // Restore result.
+  } else if (kind == kLazyDeoptFromThrow) {
+    __ Pop(R1);  // Restore stacktrace.
+    __ Pop(R0);  // Restore exception.
   }
   __ LeaveStubFrame();
   // Remove materialization arguments.
   __ add(SP, SP, Operand(R1, ASR, kSmiTagSize));
   __ Ret();
 }
 
 
-void StubCode::GenerateDeoptimizeLazyStub(Assembler* assembler) {
+// LR: return address + call-instruction-size
+// R0: result, must be preserved
+void StubCode::GenerateDeoptimizeLazyFromReturnStub(Assembler* assembler) {
   // Correct return address to point just after the call that is being
   // deoptimized.
   __ AddImmediate(LR, -CallPattern::DeoptCallPatternLengthInBytes());
   // Push zap value instead of CODE_REG for lazy deopt.
   __ LoadImmediate(IP, 0xf1f1f1f1);
   __ Push(IP);
-  GenerateDeoptimizationSequence(assembler, kLazyDeopt);
+  GenerateDeoptimizationSequence(assembler, kLazyDeoptFromReturn);
 }
 
 
+// LR: return address + call-instruction-size
+// R0: exception, must be preserved
+// R1: stacktrace, must be preserved
+void StubCode::GenerateDeoptimizeLazyFromThrowStub(Assembler* assembler) {
+  // Correct return address to point just after the call that is being
+  // deoptimized.
+  __ AddImmediate(LR, -CallPattern::DeoptCallPatternLengthInBytes());
+  // Push zap value instead of CODE_REG for lazy deopt.
+  __ LoadImmediate(IP, 0xf1f1f1f1);
+  __ Push(IP);
+  GenerateDeoptimizationSequence(assembler, kLazyDeoptFromThrow);
+}
+
+
 void StubCode::GenerateDeoptimizeStub(Assembler* assembler) {
   GenerateDeoptimizationSequence(assembler, kEagerDeopt);
 }
 
 
 static void GenerateDispatcherCode(Assembler* assembler,
                                    Label* call_target_function) {
   __ Comment("NoSuchMethodDispatch");
   // When lazily generated invocation dispatchers are disabled, the
   // miss-handler may return null.
@@ skipping 1680 matching lines @@
 }
 
 
 void StubCode::GenerateFrameAwaitingMaterializationStub(Assembler* assembler) {
   __ bkpt(0);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM