Fix uses of MaybeRecordImplicitNullCheck without special scopes
MaybeRecordImplicitNullCheck is a function which uses
CodeGenerator::RecordPcInfo() and requires an exact PC. However for ARM32/ARM64,
when CodeGenerator::RecordPcInfo() is used without VIXL special scopes (EmissionCheckScope,
ExactAssemblyScope) there is no guarantee of an exact PC. Without the special scopes VIXL might
emit veneer/literal pools affecting a PC.
The ARM32 code generator has uses of MaybeRecordImplicitNullCheck without the
special scopes.
This CL fixes missing special scopes in the ARM32/ARM64 code generators.
It also changes API to prevent such cases:
1. A variant of CodeGenerator::RecordPcInfo with native_pc as a
parameter is added. The old variant (where Assembler::CodePosition is used) is
kept and documented that Assembler::CodePosition is target-dependent and
might be imprecise.
2. CodeGenerator::MaybeRecordImplicitNullCheck is made virtual. Checks
are added to ARM32/ARM64 code generators that
MaybeRecordImplicitNullCheck is invoked within VIXL special scopes.
Test: test.py --host --optimizing --jit --gtest
Test: test.py --target --optimizing --jit
Test: run-gtests.sh
Change-Id: Ic66c16e7bdf4751cbc19a9de05846fba005b7f55
diff --git a/compiler/optimizing/code_generator_arm_vixl.h b/compiler/optimizing/code_generator_arm_vixl.h
index b541351..fae615d 100644
--- a/compiler/optimizing/code_generator_arm_vixl.h
+++ b/compiler/optimizing/code_generator_arm_vixl.h
@@ -747,6 +747,15 @@
vixl::aarch32::Register in,
vixl::aarch32::Register temp = vixl32::Register());
+ void MaybeRecordImplicitNullCheck(HInstruction* instr) final {
+ // The function must be only be called within special scopes
+ // (EmissionCheckScope, ExactAssemblyScope) which prevent generation of
+ // veneer/literal pools by VIXL assembler.
+ CHECK_EQ(GetVIXLAssembler()->ArePoolsBlocked(), true)
+ << "The function must only be called within EmissionCheckScope or ExactAssemblyScope";
+ CodeGenerator::MaybeRecordImplicitNullCheck(instr);
+ }
+
private:
// Encoding of thunk type and data for link-time generated thunks for Baker read barriers.