RFR: 8358781: C2 fails with assert "bad profile data type" when TypeProfileCasts is disabled

[Saranya Natarajan]

**Issue**
An error, `assert(data->is_ReceiverTypeData()) failed: bad profile data type`, is encountered during C2 compilation due to bad profile data. This occurs when the code is compiled with `TypeProfileCasts` option disabled. 

**Analysis** 
The assertion failure occurs in `record_profiled_receiver_for_speculation` that analyzes the profiling information in the method data to determine whether a null value has been observed in the `instanceof` operation. This information is encoded in the `BitData` during profiling. When the method identifies that a null has been seen, it proceeds to inspect the associated `ReceiverTypeData` to see if the  type check is always performed against null. However, in this scenario, the incoming profiling data is of type `BitData` rather than `ReceiverTypeData`, leading to the assertion failure. 

The profiling information for null seen for operations `aastore`, `instanceof`, and `checkcast` is recorded by the method `profile_null_seen `(in` src/hotspot/cpu/x86/templateTable_x86.cpp `). On investigating this method, it can be observed that the method data pointer is not updated for `VirtualCallData` (which is a subclass of `ReceiverTypeData`) when the `TypeProfileCasts` option is disabled. 

**Solution** 
My proposal is to inspect the `ReceiverTypeData` in function `record_profiled_receiver_for_speculation` only if `TypeProfileCasts` is enabled (this is based on the fact that the relevant method data pointer is not updated when `TypeProfileCasts` is disabled).

**Question to reviewers** 
Do you think this is a reasonable fix ?

**Testing**
GitHub Actions
tier1 to tier3 on windows-x64, linux-x64, linux-aarch64, macosx-x64, and macosx-aarch64.

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Commit messages:
 - Merge branch 'master' of https://github.com/sarannat/jdk into JDK-8358781
 - Initial Fix

Changes: https://git.openjdk.org/jdk/pull/26640/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26640&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8358781
  Stats: 11 lines in 1 file changed: 3 ins; 1 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/26640.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26640/head:pull/26640

PR: https://git.openjdk.org/jdk/pull/26640