When the `--enforce-no-safety-checks` flag is passed during the
enforcing, we avoid emitting the inlined `function_dispatcher` and we
emit instead a call to an `indirect_handle` disposable call created on
the fly to respect the ABI information on the callsite.
EnforceABI promotes global variables representing parts of the CPU
states to arguments and return values of isolated functions.
This commit enables the promotion of CSV that are used in isolated
functions only indirectly, through `ConstantExpr`s casts.
`MetaAddress` replaces all the `uint64_t` used to represent a virtual
address. Its main features are:
* It has a non-zero representation of invalid addresses.
* It supports tags to represent code that has different interpretations but
resides at the same address in memory (namely ARM vs Thumb).
* Arithmetic operations cannot overflow.
* It supports epochs, a way we intend to employ to handle self-modifying code
(i.e., different code at the same address at different times).
* It supports "address spaces", which enable handling architectures with
multiple address spaces.
* It fits in two 64-bit registers.
LLVM 9 drops the `TerminatorInst` class. This commit replaces it with
`Instruction` where possible and asserts
`Instruction::isTerminator()`. It also switches from
`TerminatorInst::successors` to `successors(TerminatorInst *)`.
* `GeneratedCodeBasicInfo::getCSVUsedByHelperCall` and
`GeneratedCodeBasicInfo::extractCSVs`: make the call argument an
`Instruction`.
* Introduce `blockByName`
* Introduce `getUniqueUser`.
* Fix linking issues.
This commit introduces the `enforce-abi` pass, which consumes the
information provided by the ABI analysis and enforces them in the
isolated functions adding actual arguments.
This commit also rewrites the logic of `ResultsPool::finalize` and
changes the semantic of `Yes` statements on arguments to `YesOrDead`.
Andrea Gussoni