I've no idea why I decided to handle TMxx differently from all the other
high/low logic operations, but it was a stupid thing to do. The high
registers aren't available as separate 32-bit registers on z10,
so subreg_h32 can't be used on a GR64 there.
I've normally been testing with z196 and with -O3 and so hadn't noticed
this until now.
llvm-svn: 195473
This just adds the basics necessary for allocating the upper words to
virtual registers (move, load and store). The move support is parameterised
in a way that makes it easy to handle zero extensions, but the associated
zero-extend patterns are added by a later patch.
The easiest way of testing this seemed to be add a new "h" register
constraint for high words. I don't expect the constraint to be useful
in real inline asms, but it should work, so I didn't try to hide it
behind an option.
llvm-svn: 191739
Another patch to avoid duplication of encoding information. Things like
NILF, NILL and NILH are used as both 32-bit and 64-bit instructions.
Here the 64-bit versions are defined as aliases of the 32-bit ones.
llvm-svn: 191369
This is the first of a few patches to reduce the dupliation of encoding
information. The return instruction is a normal BR in which one of the
registers is fixed.
llvm-svn: 191364
Lengths up to a certain threshold (currently 6 * 256) use a series of MVCs.
Lengths above that threshold use a loop to handle X*256 bytes followed
by a single MVC to handle the excess (if any). This loop will also be
needed in future when support for variable lengths is added.
Because the same tablegen classes are used to define MVC and CLC,
the patch also has the side-effect of defining a pseudo loop instruction
for CLC. That instruction isn't used yet (and wouldn't be handled correctly
if it were). I'm planning to use it soon though.
llvm-svn: 189331
If we had a store of an integer to memory, and the integer and store size
were suitable for a form of MV..., we used MV... no matter what. We could
then have sequences like:
lay %r2, 0(%r3,%r4)
mvi 0(%r2), 4
In these cases it seems better to force the constant into a register
and use a normal store:
lhi %r2, 4
stc %r2, 0(%r3, %r4)
since %r2 is more likely to be hoisted and is easier to rematerialize.
llvm-svn: 189098
This follows the same lines as the integer code. In the end it seemed
easier to have a second 4-bit mask in TSFlags to specify the compare-like
CC values. That eats one more TSFlags bit than adding a CCHasUnordered
would have done, but it feels more concise.
llvm-svn: 187883
This also fixes a bug in the predication of LR to LOCR: I'd forgotten
that with these in-place instruction builds, the implicit operands need
to be added manually. I think this was latent until now, but is tested
by int-cmp-45.c. It also adds a CC valid mask to STOC, again tested by
int-cmp-45.c.
llvm-svn: 187573
Extend r187495 to conditional loads. I split this out because the
easiest way seemed to be to force a particular operand order in
SystemZISelDAGToDAG.cpp.
llvm-svn: 187496
System z branches have a mask to select which of the 4 CC values should
cause the branch to be taken. We can invert a branch by inverting the mask.
However, not all instructions can produce all 4 CC values, so inverting
the branch like this can lead to some oddities. For example, integer
comparisons only produce a CC of 0 (equal), 1 (less) or 2 (greater).
If an integer EQ is reversed to NE before instruction selection,
the branch will test for 1 or 2. If instead the branch is reversed
after instruction selection (by inverting the mask), it will test for
1, 2 or 3. Both are correct, but the second isn't really canonical.
This patch therefore keeps track of which CC values are possible
and uses this when inverting a mask.
Although this is mostly cosmestic, it fixes undefined behavior
for the CIJNLH in branch-08.ll. Another fix would have been
to mask out bit 0 when generating the fused compare and branch,
but the point of this patch is that we shouldn't need to do that
in the first place.
The patch also makes it easier to reuse CC results from other instructions.
llvm-svn: 187495
Before the patch we took advantage of the fact that the compare and
branch are glued together in the selection DAG and fused them together
(where possible) while emitting them. This seemed to work well in practice.
However, fusing the compare so early makes it harder to remove redundant
compares in cases where CC already has a suitable value. This patch
therefore uses the peephole analyzeCompare/optimizeCompareInstr pair of
functions instead.
No behavioral change intended, but it paves the way for a later patch.
llvm-svn: 187116
These instructions are allowed to trap even if the condition is false,
so for now they are only used for "*ptr = (cond ? x : *ptr)"-style
constructs.
llvm-svn: 187111
The atomic tests assume the two-operand forms, so I've restricted them to z10.
Running and-01.ll, or-01.ll and xor-01.ll for z196 as well as z10 shows why
using convertToThreeAddress() is better than exposing the three-operand forms
first and then converting back to two operands where possible (which is what
I'd originally tried). Using the three-operand form first stops us from
taking advantage of NG, OG and XG for spills.
llvm-svn: 186683
This first step just adds definitions for SLLK, SRLK and SRAK.
The next patch will actually make use of them during codegen.
insn-bad.s tests that some form of error is reported when using these
instructions on z10. More work is needed to get the "instruction requires:
distinct-ops" that we'd ideally like, so I've stubbed that part out for now.
I'll come back and make it mandatory once the necessary changes are in.
llvm-svn: 186680
RISBG has three 8-bit operands (I3, I4 and I5). I'd originally
restricted all three to 6 bits, since that's the only range we intended
to use at the time. However, the top bit of I4 acts as a "zero" flag for
RISBG, while the top bit of I3 acts as a "test" flag for RNSBG & co.
This patch therefore allows them to have the full 8-bit range.
I've left the fifth operand as a 6-bit value for now since the
upper 2 bits have no defined meaning.
llvm-svn: 186070
Add a mapping from register-based <INSN>R instructions to the corresponding
memory-based <INSN>. Use it to cut down on the number of spill loads.
Some instructions extend their operands from smaller fields, so this
required a new TSFlags field to say how big the unextended operand is.
This optimisation doesn't trigger for C(G)R and CL(G)R because in practice
we always combine those instructions with a branch. Adding a test for every
other case probably seems excessive, but it did catch a missed optimisation
for DSGF (fixed in r185435).
llvm-svn: 185529
Rename Function->DispKey and PairType->DispSize. I'd originally used
"Function" because I thought it might be useful for other InstMappings.
However, it turns out that having two very similar instructions with the
same Function makes it pretty useless for anything other than the displacement
size key. Other InstMappings will want the key to be defined for only one
instruction in the pair.
No behavioural change intended.
llvm-svn: 185526
This is the first use of D(L,B) addressing, which required a fair bit
of surgery. For that reason, the patch just adds the instruction
definition and the associated assembler and disassembler support.
A later patch will actually make use of it for codegen.
llvm-svn: 185433
Add pseudo conditional store instructions, so that we use:
branch foo:
store
foo:
instead of:
load
branch foo:
move
foo:
store
z196 has real 32-bit and 64-bit conditional stores, but we don't use
any z196 instructions yet.
llvm-svn: 185065
This patch adds support for the CRJ and CGRJ instructions. Support for
the immediate forms will be a separate patch.
The architecture has a large number of comparison instructions. I think
it's generally better to concentrate on using the "best" comparison
instruction first and foremost, then only use something like CRJ if
CR really was the natual choice of comparison instruction. The patch
therefore opportunistically converts separate CR and BRC instructions
into a single CRJ while emitting instructions in ISelLowering.
llvm-svn: 182764
Addresses a review comment from Ulrich Weigand. No functional change intended.
I'm not sure whether the old TODO that this patch touches still holds,
but that's something we'd get to when adding a targetted scheduling
description.
llvm-svn: 182474
The SystemZ port currently relies on the order of the instruction operands
matching the order of the instruction field lists. This isn't desirable
for disassembly, where the two are matched only by name. E.g. the R1 and R2
fields of an RR instruction should have corresponding R1 and R2 operands.
The main complication is that addresses are compound operands,
and as far as I know there is no mechanism to allow individual
suboperands to be selected by name in "let Inst{...} = ..." assignments.
Luckily it doesn't really matter though. The SystemZ instruction
encoding groups all address fields together in a predictable order,
so it's just as valid to see the entire compound address operand as
a single field. That's the approach taken in this patch.
Matching by name in turn means that the operands to COPY SIGN and
CONVERT TO FIXED instructions can be given in natural order.
(It was easier to do this at the same time as the rename,
since otherwise the intermediate step was too confusing.)
No functional change intended.
llvm-svn: 181769
This adds the actual lib/Target/SystemZ target files necessary to
implement the SystemZ target. Note that at this point, the target
cannot yet be built since the configure bits are missing. Those
will be provided shortly by a follow-on patch.
This version of the patch incorporates feedback from reviews by
Chris Lattner and Anton Korobeynikov. Thanks to all reviewers!
Patch by Richard Sandiford.
llvm-svn: 181203
- Prefer short-imm instructions over ext-imm, when possible
- Prefer Z10 instructions over Z9, when possible
This hopefully should fix some dejagnu test fails on solaris
llvm-svn: 79741
Richard Sandiford