The pass emits a call to sqrt that has attribute "read-none". This call will be
converted to an ISD::FSQRT node during DAG construction, which will turn into
a mips native sqrt instruction.
llvm-svn: 183802
the Mips16 port. A few of the psuedos could either take signed
or unsigned arguments and I did not distinguish the case and improperly
rejected some valid cases that the assembler had previously accepted
when they were pure pseudos that expanded as assembly instructions.
llvm-svn: 183633
Fix an assertion when the compiler encounters big constants whose bit width is
not a multiple of 64-bits.
Although clang would never generate something like this, the backend should be
able to handle any legal IR.
<rdar://problem/13363576>
llvm-svn: 183544
pic calls. These need to be there so we don't try and use helper
functions when we call those.
As part of this, make sure that we properly exclude helper functions in pic
mode when indirect calls are involved.
llvm-svn: 182343
By default, a teq instruction is inserted after integer divide. No divide-by-zero
checks are performed if option "-mnocheck-zero-division" is used.
llvm-svn: 182306
Previously, three instructions were needed:
trunc.w.s $f0, $f2
mfc1 $4, $f0
sw $4, 0($2)
Now we need only two:
trunc.w.s $f0, $f2
swc1 $f0, 0($2)
llvm-svn: 182053
This creates stubs that help Mips32 functions call Mips16
functions which have floating point parameters that are normally passed
in floating point registers.
llvm-svn: 181972
Mips16/32 floating point interoperability.
When Mips16 code calls external functions that would normally have some
of its parameters or return values passed in floating point registers,
it needs (Mips32) helper functions to do this because while in Mips16 mode
there is no ability to access the floating point registers.
In Pic mode, this is done with a set of predefined functions in libc.
This case is already handled in llvm for Mips16.
In static relocation mode, for efficiency reasons, the compiler generates
stubs that the linker will use if it turns out that the external function
is a Mips32 function. (If it's Mips16, then it does not need the helper
stubs).
These stubs are identically named and the linker knows about these tricks
and will not create multiple copies and will delete them if they are not
needed.
llvm-svn: 181753
This option is used when the user wants to avoid emitting double precision FP
loads and stores. Double precision FP loads and stores are expanded to single
precision instructions after register allocation.
llvm-svn: 181718
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
its fields.
This removes false dependencies between DSP instructions which access different
fields of the the control register. Implicit register operands are added to
instructions RDDSP and WRDSP after instruction selection, depending on the
value of the mask operand.
llvm-svn: 181041
register.
- Define pseudo instructions which store or load ccond field of the DSP
control register.
- Emit the pseudos in MipsSEInstrInfo::storeRegToStack and loadRegFromStack.
- Expand the pseudos before callee-scan save.
- Emit instructions RDDSP or WRDSP to copy between ccond field and GPRs.
llvm-svn: 180969
Expand copy instructions between two accumulator registers before callee-saved
scan is done. Handle copies between integer GPR and hi/lo registers in
MipsSEInstrInfo::copyPhysReg. Delete pseudo-copy instructions that are not
needed.
llvm-svn: 180827
Mips32 code as Mips16 unless it can't be compiled as Mips 16. For now this
would happen as long as floating point instructions are not needed.
Probably it would also make sense to compile as mips32 if atomic operations
are needed too. There may be other cases too.
A module pass prescans the IR and adds the mips16 or nomips16 attribute
to functions depending on the functions needs.
Mips 16 mode can result in a 40% code compression by utililizing 16 bit
encoding of many instructions.
The hope is for this to replace the traditional gcc way of dealing with
Mips16 code using floating point which involves essentially using soft float
but with a library implemented using mips32 floating point. This gcc
method also requires creating stubs so that Mips32 code can interact with
these Mips 16 functions that have floating point needs. My conjecture is
that in reality this traditional gcc method would never win over this
new method.
I will be implementing the traditional gcc method also. Some of it is already
done but I needed to do the stubs to finish the work and those required
this mips16/32 mixed mode capability.
I have more ideas for to make this new method much better and I think the old
method will just live in llvm for anyone that needs the backward compatibility
but I don't for what reason that would be needed.
llvm-svn: 179185
Modifier 'D' is to use the second word of a double integer.
We had previously implemented the pure register varient of
the modifier and this patch implements the memory reference.
#include "stdio.h"
int b[8] = {0,1,2,3,4,5,6,7};
void main()
{
int i;
// The first word. Notice, no 'D'
{asm (
"lw %0,%1;"
: "=r" (i)
: "m" (*(b+4))
);}
printf("%d\n",i);
// The second word
{asm (
"lw %0,%D1;"
: "=r" (i)
: "m" (*(b+4))
);}
printf("%d\n",i);
}
llvm-svn: 179135
and mips16 on a per function basis.
Because this patch is somewhat involved I have provide an overview of the
key pieces of it.
The patch is written so as to not change the behavior of the non mixed
mode. We have tested this a lot but it is something new to switch subtargets
so we don't want any chance of regression in the mainline compiler until
we have more confidence in this.
Mips32/64 are very different from Mip16 as is the case of ARM vs Thumb1.
For that reason there are derived versions of the register info, frame info,
instruction info and instruction selection classes.
Now we register three separate passes for instruction selection.
One which is used to switch subtargets (MipsModuleISelDAGToDAG.cpp) and then
one for each of the current subtargets (Mips16ISelDAGToDAG.cpp and
MipsSEISelDAGToDAG.cpp).
When the ModuleISel pass runs, it determines if there is a need to switch
subtargets and if so, the owning pointers in MipsTargetMachine are
appropriately changed.
When 16Isel or SEIsel is run, they will return immediately without doing
any work if the current subtarget mode does not apply to them.
In addition, MipsAsmPrinter needs to be reset on a function basis.
The pass BasicTargetTransformInfo is substituted with a null pass since the
pass is immutable and really needs to be a function pass for it to be
used with changing subtargets. This will be fixed in a follow on patch.
llvm-svn: 179118
This patch initializes t9 to the handler address, but only if the relocation
model is pic. This handles the case where handler to which eh.return jumps
points to the start of the function.
Patch by Sasa Stankovic.
llvm-svn: 178588
derived class MipsSETargetLowering.
We shouldn't be generating madd/msub nodes if target is Mips16, since Mips16
doesn't have support for multipy-add/sub instructions.
llvm-svn: 178404
