There was a problem when passing structures as variable arguments.
The structures smaller than 64 bit were not left justified on MIPS64
big endian. This is now fixed by shifting the value to make it left-
justified when appropriate.
This fixes the bug http://llvm.org/bugs/show_bug.cgi?id=21608
Patch by Aleksandar Beserminji.
Differential Revision: http://reviews.llvm.org/D7881
llvm-svn: 230657
Summary:
This has most of what is needed for mips fast-isel call lowering for O32.
What is missing I will add on the next patch because this patch is already too large.
It should not be doing anything wrong but it will punt on some cases that it is basically
capable of doing.
The mechanism is there for parameters to be passed on the stack but I have not enabled it because it serves as a way for now to prevent some of the strange cases of O32 register passing that I have not fully checked yet and have some issues.
The Mips O32 abi rules are very complicated as far how data is passed in floating and integer registers.
However there is a way to think about this all very simply and this implementation reflects that.
Basically, the ABI rules are written as if everything is passed on the stack and aligned as such.
Once that is conceptually done, it is nearly trivial to reassign those locations to registers and
then all the complexity disappears.
So I have told tablegen that all the data is passed on the stack and during the lowering I fix
this by assigning to registers as per the ABI doc.
This has been my approach and you can line up what I did with the ABI document and see 1 to 1 what
is going on.
Test Plan: callabi.ll
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: jholewinski, echristo, ahatanak, llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D5714
llvm-svn: 221948
Summary:
... and after all that refactoring, it's possible to distinguish softfloat
floating point values from integers so this patch no longer breaks softfloat to
do it.
Remove direct handling of i32's in the N32/N64 ABI by promoting them to
i64. This more closely reflects the ABI documentation and also fixes
problems with stack arguments on big-endian targets.
We now rely on signext/zeroext annotations (already generated by clang) and
the Assert[SZ]ext nodes to avoid the introduction of unnecessary sign/zero
extends.
It was not possible to convert three tests to use signext/zeroext. These tests
are bswap.ll, ctlz-v.ll, ctlz-v.ll. It's not possible to put signext on a
vector type so we just accept the sign extends here for now. These tests don't
pass the vectors the same way clang does (clang puts multiple elements in the
same argument, these map 1 element to 1 argument) so we don't need to worry too
much about it.
With this patch, all known N32/N64 bugs should be fixed and we now pass the
first 10,000 tests generated by ABITest.py.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6117
llvm-svn: 221534
Summary:
In addition to the usual f128 workaround, it was also necessary to provide
a means of accessing ArgListEntry::IsFixed.
Reviewers: theraven, vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6111
llvm-svn: 221518
Summary:
In the long run, it should probably become a calling convention in its own
right but for now just move it out of
MipsISelLowering::analyzeCallOperands() so that we can drop this function
in favour of CCState::AnalyzeCallOperands().
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6085
llvm-svn: 221517
r221056 "[mips] Move F128 argument handling into MipsCCState as we did for returns. NFC."
r221058 "[mips] Fix unused variable warning introduced in r221056"
r221059 "[mips] Move all ByVal handling into CCState and tablegen-erated code. NFC."
r221061 "Renamed CCState members that appear to misspell 'Processed' as 'Proceed'. NFC."
It cuased an undefined behavior in LLVM :: CodeGen/Mips/return-vector.ll.
llvm-svn: 221081
Summary:
CCState already contains a byval implementation that is very similar to the
Mips custom code. This patch merges the custom code into the existing
common code and tablegen-erated code.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: rnk, llvm-commits
Differential Revision: http://reviews.llvm.org/D5977
llvm-svn: 221059
Summary:
There are a couple more changes to make before analyzeFormalArguments can
be merged into the standard AnalyzeFormalArguments. I've had to temporarily
poke a couple holes in MipsCCState's encapsulation to save having to make
all the required changes for this merge all at once*. These will be removed
shortly.
* We must merge our ByVal argument handling with the implementation in CCState.
This will be done over the next three patches, then the fourth will merge
analyzeFormalArguments with AnalyzeFormalArguments.
Depends on D5967
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5969
llvm-svn: 221056
Summary:
CustomCallingConv is simply a CallingConv that tablegen should not generate the
implementation for. It allows regular CallingConv's to delegate to these custom
functions. This is (currently) necessary for Mips and we cannot use CCCustom
without having to adapt to the different API that CCCustom uses.
This brings us a bit closer to being able to remove
MipsCC::analyzeCallOperands and MipsCC::analyzeFormalArguments in favour of
the common implementation.
No functional change to the targets.
Depends on D3341
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: vmedic, llvm-commits
Differential Revision: http://reviews.llvm.org/D5965
llvm-svn: 221052
Summary:
i32 is always promoted to i64 so it no longer makes sense to assign i32 to
registers.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5964
llvm-svn: 220561
Summary:
Most structs were fixed by r218451 but those of between >32-bits and
<64-bits remained broken since they were not marked with [ASZ]ExtUpper.
This patch fixes the remaining cases by using
CCPromoteToUpperBitsInType<i64> on i64's in addition to i32 and smaller.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5963
llvm-svn: 220556
Summary:
According to the ABI documentation, f128 and {f128} should both be returned
in $f0 and $f2. However, this doesn't match GCC's behaviour which is to
return f128 in $f0 and $f2, but {f128} in $f0 and $f1.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5578
llvm-svn: 219196
Summary:
This will allow us to handle f128 arguments without duplicating code from
CCState::AnalyzeFormalArguments() or CCState::AnalyzeCallOperands().
No functional change.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5292
llvm-svn: 218509
Summary:
The N32/N64 ABI's require that structs passed in registers are laid out
such that spilling the register with 'sd' places the struct at the lowest
address. For little endian this is trivial but for big-endian it requires
that structs are shifted into the upper bits of the register.
We also require that structs passed in registers have the 'inreg'
attribute for big-endian N32/N64 to work correctly. This is because the
tablegen-erated calling convention implementation only has access to the
lowered form of struct arguments (one or more integers of up to 64-bits
each) and is unable to determine the original type.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5286
llvm-svn: 218451
Summary:
The N32/N64 ABI's return f128 values in $f0 and $f2 for hard-float and $v0 and
$a0 for soft-float. The registers used in the soft-float case differ from the
usual $v0, and $v1 specified for return values.
Both cases were previously handled by duplicating the CCState::AnalyzeReturn()
and CCState::AnalyzeCallReturn() functions and modifying them to delegate to
a different assignment function for f128 and further replace the register type
for the hard-float case. There is a simpler way to do both of these.
We now use the common functions and select an initial assignment function based
on whether the original type is f128 or not. We then handle the hard-float case
using CCBitConvertToType<>.
No functional change.
Reviewers: vmedic
Reviewed By: vmedic
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5269
llvm-svn: 218036
to get the subtarget and that's accessible from the MachineFunction
now. This helps clear the way for smaller changes where we getting
a subtarget will require passing in a MachineFunction/Function as
well.
llvm-svn: 214988
Some tiny cosmetic code changes to follow. Because of the wide
ranging nature of the patch a full 24 test cycle was needed to
check against regression. This was the smallest patch I could
make to progress from the earlier ones in the series.
llvm-svn: 197350
mips16/mips32 floating point interoperability.
This patch fixes returns from mips16 functions so that if the function
was in fact called by a mips32 hard float routine, then values
that would have been returned in floating point registers are so returned.
Mips16 mode has no floating point instructions so there is no way to
load values into floating point registers.
This is needed when returning float, double, single complex, double complex
in the Mips ABI.
Helper functions in libc for mips16 are available to do this.
For efficiency purposes, these helper functions have a different calling
convention from normal Mips calls.
Registers v0,v1,a0,a1 are used to pass parameters instead of
a0,a1,a2,a3.
This is because v0,v1,a0,a1 are the natural registers used to return
floating point values in soft float. These values can then be moved
to the appropriate floating point registers with no extra cost.
The only register that is modified is ra in this call.
The helper functions make sure that the return values are in the floating
point registers that they would be in if soft float was not in effect
(which it is for mips16, though the soft float is implemented using a mips32
library that uses hard float).
llvm-svn: 181641
This calling convention was added just to handle functions which return vector
of floats. The fix committed in r165585 solves the problem.
llvm-svn: 176530
N32/64 places all variable arguments in integer registers (or on stack),
regardless of their types, but follows calling convention of non-vaarg function
when it handles fixed arguments.
llvm-svn: 144553
Petar Jovanovic