We don't handle all cases yet (see arm64-fallback.ll for an example), but this
is enough to cover most common C++ code so it's a good place to start.
llvm-svn: 294247
Well, sort of. But the lower-level code that invoke used to be using completely
botched the handling of varargs functions, which hopefully won't be possible if
they're using the same code.
llvm-svn: 293670
For some reason the exception selector register must be a pointer (that's
assumed by SDag); on the other hand, it gets moved into an IR-level type which
might be entirely different (i32 on AArch64). IRTranslator needs to be aware of
this.
llvm-svn: 293546
When the OperandsMapper creates virtual registers, it used to just create
plain scalar register with the right size. This may confuse the
instruction selector because we lose the information of the instruction
using those registers what supposed to do. The MachineVerifier complains
about that already.
With this patch, the OperandsMapper still creates plain scalar register,
but the expectation is for the mapping function to remap the type
properly. The default mapping function has been updated to do that.
rdar://problem/30231850
llvm-svn: 293362
The translation scheme is mostly cribbed from FastISel, and it's not entirely
convincing semantically. But it does seem to work in the common cases and allow
variables to be printed so it can't be all wrong.
llvm-svn: 293228
This surprisingly isn't NFC because there are patterns to select GPR
sub to SUBSWrr (rather than SUBWrr/rs); SUBS is later optimized to
SUB if NZCV is dead. From ISel's perspective, both are fine.
llvm-svn: 293010
There was a bug here where we were using p0 instead of s32 for the
selector type in the landingpad. Instead of hardcoding these types we
should get the types from the landingpad instruction directly.
Note that we replicate an assert from SDAG here to only support
two-valued landingpads.
llvm-svn: 292995
Since we're now avoiding operations using narrow scalar integer types,
we have to legalize the integer side of the FP conversions.
This requires teaching the legalizer how to do that.
llvm-svn: 292828
Since r279760, we've been marking as legal operations on narrow integer
types that have wider legal equivalents (for instance, G_ADD s8).
Compared to legalizing these operations, this reduced the amount of
extends/truncates required, but was always a weird legalization decision
made at selection time.
So far, we haven't been able to formalize it in a way that permits the
selector generated from SelectionDAG patterns to be sufficient.
Using a wide instruction (say, s64), when a narrower instruction exists
(s32) would introduce register class incompatibilities (when one narrow
generic instruction is selected to the wider variant, but another is
selected to the narrower variant).
It's also impractical to limit which narrow operations are matched for
which instruction, as restricting "narrow selection" to ranges of types
clashes with potentially incompatible instruction predicates.
Concerns were also raised regarding MIPS64's sign-extended register
assumptions, as well as wrapping behavior.
See discussions in https://reviews.llvm.org/D26878.
Instead, legalize the operations.
Should we ever revert to selecting these narrow operations, we should
try to represent this more accurately: for instance, by separating
a "concrete" type on operations, and an "underlying" type on vregs, we
could move the "this narrow-looking op is really legal" decision to the
legalizer, and let the selector use the "underlying" vreg type only,
which would be guaranteed to map to a register class.
In any case, we eventually should mitigate:
- the performance impact by selecting no-op extract/truncates to COPYs
(which we currently do), and the COPYs to register reuses (which we
don't do yet).
- the compile-time impact by optimizing away extract/truncate sequences
in the legalizer.
llvm-svn: 292827
Big functions with large vreg # are quite unwieldy to update.
Change it to have one function per test (it does increase boilerplate,
but makes the core hopefully more readable and maintanable).
llvm-svn: 292552
Big functions with large vreg # are quite unwieldy to update. This test
also relied on legal s8 operations which we're considering removing.
Change it to have one function per test (it does increase boilerplate,
but makes the core hopefully more readable and maintanable), and use
100% legal operations throughout.
llvm-svn: 292551
Some platforms (notably iOS) use a different calling convention for unnamed vs
named parameters in varargs functions, so we need to keep track of this
information when translating calls.
Since not many platforms are involved, the guts of the special handling is in
the ValueHandler class (with a generic implementation that should work for most
targets).
llvm-svn: 292283
Correctly populating Machine PHIs relies on knowing exactly how the IR level
CFG was lowered to MachineIR. This needs to be tracked by any translation
phases that meddle (currently only SwitchInst handling).
This reapplies r291973 which was reverted because of testing failures. Fixes:
+ Don't return an ArrayRef to a local temporary.
+ Incorporate Kristof's suggested comment improvements.
llvm-svn: 292278
This reverts commit r291973.
The test fails in a Release build with LLVM_BUILD_GLOBAL_ISEL enabled.
AFAICT, llc segfaults. I'll add a few more details to the original
commit.
llvm-svn: 292061
Correctly populating Machine PHIs relies on knowing exactly how the IR level
CFG was lowered to MachineIR. This needs to be tracked by any translation
phases that meddle (currently only SwitchInst handling).
llvm-svn: 291973
To make this work, pointers from the MachineBasicBlock to the LLVM-IR-level
basic blocks need to be initialized, as the AsmPrinter uses this link to be
able to print out labels for the basic blocks that are address-taken.
Most of the changes in this commit are about adapting existing tests to include
the basic block name that is now printed out in the MIR format, now that the
name becomes available as the link to the LLVM-IR basic block is initialized.
The relevant test change for the functionality added in this patch are the
added "(address-taken)" strings in
test/CodeGen/AArch64/GlobalISel/arm64-irtranslator.ll.
Differential Revision: https://reviews.llvm.org/D28123
llvm-svn: 291105
This commit does this using a trivial chain of conditional branches. In the
future, we probably want to reuse the optimized switch lowering used in
SelectionDAG.
Differential Revision: https://reviews.llvm.org/D28176
llvm-svn: 291099
Target specific instructions have requirements that are not compatible
with what we want to test here. Namely, target specific instructions
must have their operands properly mapped on register classes.
llvm-svn: 290379
The InstructionSelect pass will not look at target specific instructions
since they are already selected. As a result, the operands of target
specific instructions must be properly constrained, because it is not
going to fix them.
This fixes invalid register classes on call instruction.
llvm-svn: 290377
The IRTranslator uses an additional block before the LLVM-IR entry block
to perform all the ABI lowering and the constant hoisting. Thus, this
block is the actual entry block and it falls through the LLVM-IR entry
block. However, with such representation, we end up with two basic
blocks that are not maximal.
Therefore, this patch adds a bit of canonicalization by merging both the
LLVM-IR entry block and the ABI lowering/constants hoisting into one
block, making the resulting block more likely to be maximal (indeed the
LLVM-IR entry block might not have been maximal).
llvm-svn: 289891
We were using the correct pseudo-instruction, but because the operand's flags
weren't set correctly we still ended up emitting incorrect relocations during
MC lowering.
llvm-svn: 289566
Supporting them properly is a reasonably complex chunk of work, so to allow bot
testing before then we should at least be able to fall back to DAG ISel.
llvm-svn: 289150
ConstantExpr instances were emitting code into the current block rather than
the entry block. This meant they didn't necessarily dominate all uses, which is
clearly wrong.
llvm-svn: 288985
MachineIRBuilder had weird before/after and beginning/end flags for the insert
point. Unfortunately the non-default means that instructions will be inserted
in reverse order which is almost never what anyone wants.
Really, I think we just want (like IRBuilder has) the ability to insert at any
C++ iterator-style point (i.e. before any instruction or before MBB.end()). So
this fixes MIRBuilders to behave like IRBuilders in this respect.
llvm-svn: 288980
We were rounding size in bits down rather than up, leading to 0-sized slots for
i1 (assert!) and bugs for other types not byte-aligned.
llvm-svn: 288848
There were two problems:
+ AArch64 was reusing random data from its binary op tables, which is
complete nonsense for G_SEQUENCE.
+ Even when AArch64 gave up and said it couldn't handle G_SEQUENCE,
the generic code asserted.
llvm-svn: 288836
It'll almost immediately fail because it always tries to half/double the size
until it finds a legal one. Unfortunately, this triggers an assertion
preventing the DAG fallback from being possible.
llvm-svn: 288834
The function used to finish off PHIs by adding the relevant basic blocks can
fail if we're aborting and still don't actually have the needed
MachineBasicBlocks. So avoid trying in that case.
llvm-svn: 288727
When the entry block was empty after arg lowering, we were always placing
constants at the end. This is probably hamrless while translating the same
block, but horribly wrong once its terminator has been translated. So switch to
inserting at the beginning.
llvm-svn: 288720
Tim Northover