Fix assertions wrt concurrent OSR.

src/a64/full-codegen-a64.cc

Index: src/a64/full-codegen-a64.cc
diff --git a/src/a64/full-codegen-a64.cc b/src/a64/full-codegen-a64.cc
index c95a01add5c2227560e431be9ac7378ef98b99da..935f74f4ef429a78aaf36ce332e262ef231dc5a8 100644
--- a/src/a64/full-codegen-a64.cc
+++ b/src/a64/full-codegen-a64.cc
@@ -4868,8 +4868,6 @@ void BackEdgeTable::PatchAt(Code* unoptimized_code,
       //  ... more instructions.
       //  ok-label
       // Jump offset is 6 instructions.
-      ASSERT(Instruction::Cast(branch_address)
-                 ->IsNop(Assembler::INTERRUPT_CODE_NOP));
       patcher.b(6, pl);
       break;
     case ON_STACK_REPLACEMENT:
@@ -4878,9 +4876,6 @@ void BackEdgeTable::PatchAt(Code* unoptimized_code,
       //  .. .. .. ..       mov x0, x0 (NOP)
       //  .. .. .. ..       ldr x16, pc+<on-stack replacement address>
       //  .. .. .. ..       blr x16
-      ASSERT(Instruction::Cast(branch_address)->IsCondBranchImm());
-      ASSERT(Instruction::Cast(branch_address)->ImmPCOffset() ==
-             6 * kInstructionSize);

[Yang, 2014/03/20 13:33:05]

Those assertions are bogus. We want to be able to go from any state to any other
state. For example from ON_STACK_REPLACEMENT to OSR_AFTER_STACK_CHECK.

[ulan, 2014/03/20 13:50:46]

Let's fix the asserts instead of removing them. =)
Could you move the three asserts above switch and combine them?

       patcher.nop(Assembler::INTERRUPT_CODE_NOP);
       break;
   }