[ARM] Skip inline asm memory operands in DAGToDAGISel

Authored by rovka on Jul 20 2016, 2:48 AM.


[ARM] Skip inline asm memory operands in DAGToDAGISel

Retry r275776 (no changes, we suspect the issue was with another commit).

The current logic for handling inline asm operands in DAGToDAGISel interprets
the operands by looking for constants, which should represent the flags
describing the kind of operand we're dealing with (immediate, memory, register
def etc). The operands representing actual data are skipped only if they are
non-const, with the exception of immediate operands which are skipped explicitly
when a flag describing an immediate is found.

The oversight is that memory operands may be const too (e.g. for device drivers
reading a fixed address), so we should explicitly skip the operand following a
flag describing a memory operand. If we don't, we risk interpreting that
constant as a flag, which is definitely not intended.

Fixes PR26038

Differential Revision: https://reviews.llvm.org/D22103

llvm-svn: 276101


rovkaJul 20 2016, 2:48 AM
Differential Revision
D22103: [ARM] Skip inline asm memory operands in DAGToDAGISel
rG10f8472771c0: [docs] fix cmake code-block warning