Backwards compatibility with 'gas'. #imm is the preferered and documented
syntax, but lots of existing code uses the '$' prefix, so we should
support it if we can.
llvm-svn: 146285
When the immediate operand of an AND or BIC instruction isn't representable
in the immediate field of the instruction, but the bitwise negation of the
immediate is, assemble the instruction as the inverse operation instead
with the inverted immediate as the operand.
rdar://10550057
llvm-svn: 146283
Refactor the instructions into fixed writeback and register-stride
writeback variants to simplify the offset operand (no more optional
register operand using reg0). This is a simpler representation and allows
the assembly parser to more easily handle these instructions.
Add tests for the instruction variants now supported.
llvm-svn: 146278
It is not used any more. We are tracking inline assembly misalignments
directly through the BBInfo.Unalign and KnownBits fields.
A simple conservative size estimate is not good enough since it can
cause alignment padding to be underestimated.
llvm-svn: 146124
Compute alignment padding before and after basic blocks dynamically.
Heed basic block alignment.
This simplifies bookkeeping because we don't have to constantly add and
remove padding from BBInfo.Size. It also makes it possible to track the
extra known alignment bits we get after a tBR_JTr terminator and when
entering an aligned basic block.
This makes the ARMConstantIslandPass aware of aligned basic blocks.
It is tricky to model block alignment correctly when dealing with inline
assembly and tBR_JTr instructions that have variable size. If inline
assembly turns out to be smaller than expected, that may cause following
alignment padding to be larger than expected. This could cause constant
pool entries to move out of range.
To avoid that problem, we use the worst case alignment padding following
inline assembly. This may cause slightly suboptimal constant island
placement in aligned basic blocks following inline assembly. Normal
functions should be unaffected.
llvm-svn: 146118
When the file isn't being built with subsections-via-symbols, symbol
differences involving non-local symbols can be resolved more aggressively.
Needed for gas compatibility.
llvm-svn: 146054
generator to it. For non-bundle instructions, these behave exactly the same
as the MC layer API.
For properties like mayLoad / mayStore, look into the bundle and if any of the
bundled instructions has the property it would return true.
For properties like isPredicable, only return true if *all* of the bundled
instructions have the property.
For properties like canFoldAsLoad, isCompare, conservatively return false for
bundles.
llvm-svn: 146026
The block offset can be computed from the previous block. That is more
robust than keeping track of a delta.
Eliminate one redundant AdjustBBOffsetsAfter call.
llvm-svn: 146018
1. Added opcode BUNDLE
2. Taught MachineInstr class to deal with bundled MIs
3. Changed MachineBasicBlock iterator to skip over bundled MIs; added an iterator to walk all the MIs
4. Taught MachineBasicBlock methods about bundled MIs
llvm-svn: 145975
This pseudo-instruction contains a .align directive in its expansion, so
the total size may vary by 2 bytes.
It is too difficult to accurately keep track of this alignment
directive, just use the worst-case size instead.
llvm-svn: 145971