sub-register indices and outputs a single super register which is formed from
a consecutive sequence of registers.
This is used as register allocation / coalescing aid and it is useful to
represent instructions that output register pairs / quads. For example,
v1024, v1025 = vload <address>
where v1024 and v1025 forms a register pair.
This really should be modelled as
v1024<3>, v1025<4> = vload <address>
but it would violate SSA property before register allocation is done.
Currently we use insert_subreg to form the super register:
v1026 = implicit_def
v1027 - insert_subreg v1026, v1024, 3
v1028 = insert_subreg v1027, v1025, 4
...
= use v1024
= use v1028
But this adds pseudo live interval overlap between v1024 and v1025.
We can now modeled it as
v1024, v1025 = vload <address>
v1026 = REG_SEQUENCE v1024, 3, v1025, 4
...
= use v1024
= use v1026
After coalescing, it will be
v1026<3>, v1025<4> = vload <address>
...
= use v1026<3>
= use v1026
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102815 91177308-0d34-0410-b5e6-96231b3b80d8
code, and to eliminate the need for the SelectionDAGBuilder
state to be live during CodeGenAndEmitDAG calls.
Call SDB->clear() before CodeGenAndEmitDAG calls instead of
before it, and move the CurDAG->clear() out of SelectionDAGBuilder,
which doesn't own the DAG, and into CodeGenAndEmitDAG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102814 91177308-0d34-0410-b5e6-96231b3b80d8
were still inlining self-recursive functions into other functions.
Inlining a recursive function into itself has the potential to
reduce recursion depth by a factor of 2, inlining a recursive
function into something else reduces recursion depth by exactly
1. Since inlining a recursive function into something else is a
weird form of loop peeling, turn this off.
The deleted testcase was added by Dale in r62107, since then
we're leaning towards not inlining recursive stuff ever. In any
case, if we like inlining recursive stuff, it should be done
within the recursive function itself to get the algorithm
recursion depth win.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102798 91177308-0d34-0410-b5e6-96231b3b80d8
indexes could be of a different value type. Or not even using the same SDNode
for the constant (weird, I know). Compare the actual values instead of the
pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102791 91177308-0d34-0410-b5e6-96231b3b80d8
instruction selection is done; it's confusing to see parts of it printed,
while other parts are omitted, along the way.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102771 91177308-0d34-0410-b5e6-96231b3b80d8
call that might throw. The landing pad assumes that all registers are in stack
slots.
We used to spill those dirty CSRs after the call, and the stack slots would be
wrong when arriving at the landing pad.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102770 91177308-0d34-0410-b5e6-96231b3b80d8
MachineFunction::DefaultDebugLoc. We now use the same technique as
DwarfDebug::beginFunction to find the starting line number for a
function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102679 91177308-0d34-0410-b5e6-96231b3b80d8
of different register classes. e.g.
%reg1048:3<def> = EXTRACT_SUBREG %RAX<kill>, 3
Where %reg1048 is a GR32 register. This is not impossible to handle, but it is
pretty hard and very rare.
This should unbreak the dragonegg builder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102672 91177308-0d34-0410-b5e6-96231b3b80d8