In rare cases the dead definition elimination pass code can cause illegal cmn
instructions when it replaces dead registers on instructions that use
unmaterialized frame indexes. This patch disables the dead definition
optimization for instructions which include frame index operands.
rdar://16438284
llvm-svn: 206208
There was one definite issue in ARM64 (the off-by-1 check for whether
a shift could be folded in) and one difference that is probably
correct: ARM64 didn't fold nodes with multiple uses into the
arithmetic operations unless optimising for code size.
llvm-svn: 206168
Originally the cost model would give up for large constants and just return the
maximum cost. This is not what we want for constant hoisting, because some of
these constants are large in bitwidth, but are still cheap to materialize.
This commit fixes the cost model to either return TCC_Free if the cost cannot be
determined, or accurately calculate the cost even for large constants
(bitwidth > 128).
This fixes <rdar://problem/16591573>.
llvm-svn: 206100
MCDisassembler has an MCSymbolizer member that is meant to take care of
symbolizing during disassembly, but it also has several methods that enable the
disassembler to do symbolization internally (i.e. without an attached symbolizer
object). There is no need for this duplication, but ARM64 had been making use of
it. This patch moves the ARM64 symbolization logic out of ARM64Disassembler and
into an ARM64ExternalSymbolizer class, and removes the duplicated MCSymbolizer
functionality from the MCDisassembler interface. Symbolization will now be
done exclusively through MCSymbolizers.
There should be no impact on disassembly for any platform, but this allows us to
tidy up the MCDisassembler interface and simplify the process of (and invariants
related to) disassembler setup.
llvm-svn: 206063
Also updated as many loops as I could find using df_begin/idf_begin -
strangely I found no uses of idf_begin. Is that just used out of tree?
Also a few places couldn't use df_begin because either they used the
member functions of the depth first iterators or had specific ordering
constraints (I added a comment in the latter case).
Based on a patch by Jim Grosbach. (Jim - you just had iterator_range<T>
where you needed iterator_range<idf_iterator<T>>)
llvm-svn: 206016
GCC 4.8 complains with:
warning: enumeral and non-enumeral type in conditional expression
Although this is silly and harmless in this case, add an explicit cast to
silence the warning.
llvm-svn: 205949
The immediate cost calculation code was hitting an assertion in the included
test case, because APInt was still internally 128-bits. Truncating it to 64-bits
fixed the issue.
Fixes <rdar://problem/16572521>.
llvm-svn: 205947