Changing the diagnostic message for out of range branch targets in 191686 broke the tests.
The diagnostic message for out of range branch targets was changed to be more consistent with the other diagnostics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191691 91177308-0d34-0410-b5e6-96231b3b80d8
The long encoding for Thumb2 unconditional branches is broken.
Additionally, there is no range checking for target operands; as such
for instructions originating in assembly code, only short Thumb encodings
are generated, regardless of the bitsize needed for the offset.
Adding range checking is non trivial due to the representation of Thumb
branch instructions. There is no true difference between conditional and
unconditional branches in terms of operands and syntax - even unconditional
branches have a predicate which is expected to match that of the IT block
they are in. Yet, the encodings and the permitted size of the offset differ.
Due to this, for any mnemonic there are really 4 encodings to choose for.
The problem cannot be handled in the parser alone or by manipulating td files.
Because the parser builds first a set of match candidates and then checks them
one by one, whatever tablegen-only solution might be found will ultimately be
dependent of the parser's evaluation order. What's worse is that due to the fact
that all branches have the same syntax and the same kinds of operands, that
order is governed by the lexicographical ordering of the names of operand
classes...
To circumvent all this, any necessary disambiguation is added to the instruction
validation pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188067 91177308-0d34-0410-b5e6-96231b3b80d8
Unfortunately this addresses two issues (by the time I'd disentangled the logic
it wasn't worth putting it back to half-broken):
+ Coprocessor instructions should all be predicable in Thumb mode.
+ BKPT should never be predicable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184965 91177308-0d34-0410-b5e6-96231b3b80d8
As an example of how the custom DiagnosticType can be used to provide
better operand-mismatch diagnostics, add a custom diagnostic for
the imm0_15 operand class used for several system instructions.
Update the tests to expect the improved diagnostic.
rdar://8987109
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159051 91177308-0d34-0410-b5e6-96231b3b80d8
