The basic idea is that all these algorithms are computing the longest paths from the root node or to the exit node. Therefore the existing implementation that uses and iterative and potentially
exponential algorithm was changed to a well-known graph algorithm based on dynamic programming. It has a linear run-time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47884 91177308-0d34-0410-b5e6-96231b3b80d8
generic & x86 versions; change generic to follow x86
and improve comments. Add PPC version (not right
for non-Darwin.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47734 91177308-0d34-0410-b5e6-96231b3b80d8
same size as an int type by doing a bitconvert of
load/store of the int type (same algorithm as floating point).
This makes them work for ppc Altivec. There was some
code that purported to handle loads of (some) vectors
by splitting them into two smaller vectors, but getExtLoad
rejects subvector loads, so this could never have worked;
the patch removes it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47696 91177308-0d34-0410-b5e6-96231b3b80d8
approach taken is different to that in LegalizeDAG
when it is a question of expanding or promoting the
result type: for example, if extracting an i64 from
a <2 x i64>, when i64 needs expanding, it bitcasts
the vector to <4 x i32>, extracts the appropriate
two i32's, and uses those for the Lo and Hi parts.
Likewise, when extracting an i16 from a <4 x i16>,
and i16 needs promoting, it bitcasts the vector to
<2 x i32>, extracts the appropriate i32, twiddles
the bits if necessary, and uses that as the promoted
value. This puts more pressure on bitcast legalization,
and I've added the appropriate cases. They needed to
be added anyway since users can generate such bitcasts
too if they want to. Also, when considering various
cases (Legal, Promote, Expand, Scalarize, Split) it is
a pain that expand can correspond to Expand, Scalarize
or Split, so I've changed the LegalizeTypes enum so it
lists those different cases - now Expand only means
splitting a scalar in two.
The code produced is the same as by LegalizeDAG for
all relevant testcases, except for
2007-10-31-extractelement-i64.ll, where the code seems
to have improved (see below; can an expert please tell
me if it is better or not).
Before < vs after >.
< subl $92, %esp
< movaps %xmm0, 64(%esp)
< movaps %xmm0, (%esp)
< movl 4(%esp), %eax
< movl %eax, 28(%esp)
< movl (%esp), %eax
< movl %eax, 24(%esp)
< movq 24(%esp), %mm0
< movq %mm0, 56(%esp)
---
> subl $44, %esp
> movaps %xmm0, 16(%esp)
> pshufd $1, %xmm0, %xmm1
> movd %xmm1, 4(%esp)
> movd %xmm0, (%esp)
> movq (%esp), %mm0
> movq %mm0, 8(%esp)
< subl $92, %esp
< movaps %xmm0, 64(%esp)
< movaps %xmm0, (%esp)
< movl 12(%esp), %eax
< movl %eax, 28(%esp)
< movl 8(%esp), %eax
< movl %eax, 24(%esp)
< movq 24(%esp), %mm0
< movq %mm0, 56(%esp)
---
> subl $44, %esp
> movaps %xmm0, 16(%esp)
> pshufd $3, %xmm0, %xmm1
> movd %xmm1, 4(%esp)
> movhlps %xmm0, %xmm0
> movd %xmm0, (%esp)
> movq (%esp), %mm0
> movq %mm0, 8(%esp)
< subl $92, %esp
< movaps %xmm0, 64(%esp)
---
> subl $44, %esp
< movl 16(%esp), %eax
< movl %eax, 48(%esp)
< movl 20(%esp), %eax
< movl %eax, 52(%esp)
< movaps %xmm0, (%esp)
< movl 4(%esp), %eax
< movl %eax, 60(%esp)
< movl (%esp), %eax
< movl %eax, 56(%esp)
---
> pshufd $1, %xmm0, %xmm1
> movd %xmm1, 4(%esp)
> movd %xmm0, (%esp)
> movd %xmm1, 12(%esp)
> movd %xmm0, 8(%esp)
< subl $92, %esp
< movaps %xmm0, 64(%esp)
---
> subl $44, %esp
< movl 24(%esp), %eax
< movl %eax, 48(%esp)
< movl 28(%esp), %eax
< movl %eax, 52(%esp)
< movaps %xmm0, (%esp)
< movl 12(%esp), %eax
< movl %eax, 60(%esp)
< movl 8(%esp), %eax
< movl %eax, 56(%esp)
---
> pshufd $3, %xmm0, %xmm1
> movd %xmm1, 4(%esp)
> movhlps %xmm0, %xmm0
> movd %xmm0, (%esp)
> movd %xmm1, 12(%esp)
> movd %xmm0, 8(%esp)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47672 91177308-0d34-0410-b5e6-96231b3b80d8
operand of a VECTOR_SHUFFLE. The mask is a
vector of constant integers. The code in
LegalizeDAG doesn't bother to legalize the
mask, since it's basically just storage for
a bunch of constants, however LegalizeTypes
is more picky. The problem is that there may
not exist any legal vector-of-integers type
with a legal element type, so it is impossible
to create a legal mask! Unless of course you
cheat by creating a BUILD_VECTOR where the
operands have a different type to the element
type of the vector being built... This is
pretty ugly but works - all relevant tests in
the testsuite pass, and produce the same
assembler with and without LegalizeTypes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47670 91177308-0d34-0410-b5e6-96231b3b80d8
Change several cases in SimplifyDemandedMask that don't ever do any
simplifying to reuse the logic in ComputeMaskedBits instead of
duplicating it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47648 91177308-0d34-0410-b5e6-96231b3b80d8
CodeGen/PowerPC/illegal-element-type.ll): suppose
a node X is processed, and processing maps it to
a node Y. Then X continues to exist in the DAG,
but with no users. While processing some other
node, a new node may be created that happens to
be equal to X, and thus X will be reused rather
than a truly new node. This can cause X to
"magically reappear", and since it is in the
Processed state in will not be reprocessed, so
at the end of type legalization the illegal node
X can still be present. The solution is to replace
X with Y whenever X gets resurrected like this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47601 91177308-0d34-0410-b5e6-96231b3b80d8
after legalize. Just because a constant is legal (e.g. 0.0 in SSE)
doesn't mean that its negated value is legal (-0.0). We could make
this stronger by checking to see if the negated constant is actually
legal post negation, but it doesn't seem like a big deal.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47591 91177308-0d34-0410-b5e6-96231b3b80d8
out of illegal elements (BUILD_VECTOR). Uses and beefs
up BUILD_PAIR, though it didn't really have to. Like
most of LegalizeTypes, does not support soft-float.
This cures all "make check" vector building failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47537 91177308-0d34-0410-b5e6-96231b3b80d8
early clobbers if the clobber list contains a *register* not some thing
like {memory}, {dirflag} etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47457 91177308-0d34-0410-b5e6-96231b3b80d8
any, we force sdisel to do all regalloc for an asm. This
leads to gross but correct codegen.
This fixes the rest of PR2078.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47454 91177308-0d34-0410-b5e6-96231b3b80d8
inline asms.
Fix PR2078 by marking aliases of registers used when a register is
marked used. This prevents EAX from being allocated when AX is listed
in the clobber set for the asm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47426 91177308-0d34-0410-b5e6-96231b3b80d8
