[x86/Linux] Do NOT use pXXX fields (#9121)
* [x86/Linux] Do NOT use pXXX fields
* Fix x86/Windows build error
* Fix another x86/Windows build error
* Fix typo
* Do NOT trash EBP
* Reflect the original semantics of EHContext::UpdateFrame
* Unify ReadXXX/LocateXXX into GetXXXLocation, and RestoreXXX/TrashXXX into SetXXXLocation
* Revert the order of pXXX fields
* Revise cgenx86.cpp
* Revert unnecessary changes
* Remove direct accesses to CALLEE_SAVED_REGISTERS_TAG
* Do NOT update pCurrentContext inside SetXXXLocation
* Update RegPtr via offset
* Unify REG_METHODS (and revise UpdateRegDisplay methods accordingly)
* Revise per feedback
* Fix x86/Windows build error
13 files changed: