when the condition is constant. This optimization shouldn't be
necessary, because codegen shouldn't be able to find dead control
paths that the IR-level optimizer can't find. And it's undesirable,
because it encourages bugpoint to leave "br i1 false" branches
in its output. And it wasn't updating the CFG.
I updated all the tests I could, but some tests are too reduced
and I wasn't able to meaningfully preserve them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106748 91177308-0d34-0410-b5e6-96231b3b80d8
CoalescerPair can determine if a copy can be coalesced, and which register gets
merged away. The old logic in SimpleRegisterCoalescing had evolved into
something a bit too convoluted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106701 91177308-0d34-0410-b5e6-96231b3b80d8
void t(int *cp0, int *cp1, int *dp, int fmd) {
int c0, c1, d0, d1, d2, d3;
c0 = (*cp0++ & 0xffff) | ((*cp1++ << 16) & 0xffff0000);
c1 = (*cp0++ & 0xffff) | ((*cp1++ << 16) & 0xffff0000);
/* ... */
}
It code gens into something pretty bad. But with this change (analogous to the
X86 back-end), it will use ldm and generate few instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106693 91177308-0d34-0410-b5e6-96231b3b80d8
Given the pattern below as an example:
list<dag> Pattern = [(set RC:$dst, (v4f32 (shufp:src3 RC:$src1,
(mem_frag addr:$src2))))];
The right reference resolving should lead to:
list<dag> Pattern = [(set VR128:$dst, (v4f32 (shufp:src3 VR128:$src1,
(mem_frag addr:$src2))))];
But was yielding:
list<dag> Pattern = [(set VR128:$dst, (v4f32 (shufp VR128:$src1,
(mem_frag addr:$src2))))];
Fix this by passing the right name when creating a new DagInit node.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106670 91177308-0d34-0410-b5e6-96231b3b80d8
into the same node, but with different non-memory operands, we need to replace
the memory operands after it's finished morphing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106643 91177308-0d34-0410-b5e6-96231b3b80d8
Measurements show that it does not speed up coalescing, so there is no reason
the keep the added complexity around.
Also clean out some unused methods and static functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106548 91177308-0d34-0410-b5e6-96231b3b80d8
opportunities. For example, this lets it emit this:
movq (%rax), %rcx
addq %rdx, %rcx
instead of this:
movq %rdx, %rcx
addq (%rax), %rcx
in the case where %rdx has subsequent uses. It's the same number
of instructions, and usually the same encoding size on x86, but
it appears faster, and in general, it may allow better scheduling
for the load.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106493 91177308-0d34-0410-b5e6-96231b3b80d8
This allows the fast regiser allocator to remove redundant
register moves.
Update a set of tests that depend on the register allocator
to be linear scan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106420 91177308-0d34-0410-b5e6-96231b3b80d8
use sharing map. The reconcileNewOffset logic already forces a
separate use if the kinds differ, so incorporating the kind in the
key means we can track more sharing opportunities.
More sharing means fewer total uses to track, which means smaller
problem sizes, which means the conservative throttles don't kick
in as often.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106396 91177308-0d34-0410-b5e6-96231b3b80d8
assuming that loops are in canonical form, as ScalarEvolution doesn't
depend on LoopSimplify itself. Also, with indirectbr not all loops can
be simplified. This fixes PR7416.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106389 91177308-0d34-0410-b5e6-96231b3b80d8
