INC64_32r and INC64_16r, because these instructions are encoded
differently on x86-64. This fixes JIT regressions on x86-64 in
kimwitu++ and others.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66207 91177308-0d34-0410-b5e6-96231b3b80d8
to Eli for pointing out that these forms don't ignore the high bits of
their index operands, and as such are not immediately suitable for use
by isel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62194 91177308-0d34-0410-b5e6-96231b3b80d8
into their left operand, rather than their right. Do this
by commuting the operands and inverting the condition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61842 91177308-0d34-0410-b5e6-96231b3b80d8
which are identical to the original patterns.
- Change the multiply with overflow so that we distinguish between signed and
unsigned multiplication. Currently, unsigned multiplication with overflow
isn't working!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60963 91177308-0d34-0410-b5e6-96231b3b80d8
ISD::ADD to emit an implicit EFLAGS. This was horribly broken. Instead, replace
the intrinsic with an ISD::SADDO node. Then custom lower that into an
X86ISD::ADD node with a associated SETCC that checks the correct condition code
(overflow or carry). Then that gets lowered into the correct X86::ADDOvf
instruction.
Similar for SUB and MUL instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60915 91177308-0d34-0410-b5e6-96231b3b80d8
target-independent way of determining overflow on multiplication. It's very
tricky. Patch by Zoltan Varga!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60800 91177308-0d34-0410-b5e6-96231b3b80d8
the conditional for the BRCOND statement. For instance, it will generate:
addl %eax, %ecx
jo LOF
instead of
addl %eax, %ecx
; About 10 instructions to compare the signs of LHS, RHS, and sum.
jl LOF
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60123 91177308-0d34-0410-b5e6-96231b3b80d8
use a SUB instruction instead of an ADD, because -128 can be
encoded in an 8-bit signed immediate field, while +128 can't be.
This avoids the need for a 32-bit immediate field in this case.
A similar optimization applies to 64-bit adds with 0x80000000,
with the 32-bit signed immediate field.
To support this, teach tablegen how to handle 64-bit constants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57663 91177308-0d34-0410-b5e6-96231b3b80d8
shift counts, and patterns that match dynamic shift counts
when the subtract is obscured by a truncate node.
Add DAGCombiner support for recognizing rotate patterns
when the shift counts are defined by truncate nodes.
Fix and simplify the code for commuting shld and shrd
instructions to work even when the given instruction doesn't
have a parent, and when the caller needs a new instruction.
These changes allow LLVM to use the shld, shrd, rol, and ror
instructions on x86 to replace equivalent code using two
shifts and an or in many more cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57662 91177308-0d34-0410-b5e6-96231b3b80d8
the predicates by extending simple predicates to create
more complex predicates instead of duplicating the logic
for the simple predicates.
This doesn't reduce much redundancy in DAGISelEmitter.cpp's
generated source yet; that will require improvements to
DAGISelEmitter.cpp's instruction sorting, to make it more
effectively group nodes with similar predicates together.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57565 91177308-0d34-0410-b5e6-96231b3b80d8
parameters instead of raw Constants. This prevents the constants from
being selected by the isel pass, fixing PR2735.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57385 91177308-0d34-0410-b5e6-96231b3b80d8
This allows the 64-bit forms to use+def RSP instead of ESP. This
doesn't fix any real bugs today, but it is more precise and it
makes the debug dumps on x86-64 look more consistent.
Also, add some comments describing the CALL instructions' physreg
operand uses and defs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56925 91177308-0d34-0410-b5e6-96231b3b80d8
- Add linkage to SymbolSDNode (default to external).
- Change ISD::ExternalSymbol to ISD::Symbol.
- Change ISD::TargetExternalSymbol to ISD::TargetSymbol
These changes pave the way to allowing SymbolSDNodes with non-external linkage.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56249 91177308-0d34-0410-b5e6-96231b3b80d8
with ConstantInt. This led to fixing a bug in TargetLowering.cpp
using getValue instead of getAPIntValue.
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ATOMIC_LOAD_ADD_{8,16,32,64} instead of ATOMIC_LOAD_ADD.
Increased the Hardcoded Constant OpActionsCapacity to match.
Large but boring; no functional change.
This is to support partial-word atomics on ppc; i8 is
not a valid type there, so by the time we get to lowering, the
ATOMIC_LOAD nodes looks the same whether the type was i8 or i32.
The information can be added to the AtomicSDNode, but that is the
largest SDNode; I don't fully understand the SDNode allocation,
but it is sensitive to the largest node size, so increasing
that must be bad. This is the alternative.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55457 91177308-0d34-0410-b5e6-96231b3b80d8
instructions that define the full 32 or 64-bit value. When anyexting
from i8 to i16 or i32, it's not necessary to zero out the high
portion of the register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55190 91177308-0d34-0410-b5e6-96231b3b80d8
out of X86ISelDAGToDAG.cpp C++ code and into tablegen code.
Among other things, using tablegen for these things makes them
friendlier to FastISel.
Tablegen can handle the case of i8 subregs on x86-32, but currently
the C++ code for that case uses MVT::Flag in a tricky way, and it
happens to schedule better in some cases. So for now, leave the
C++ code in place to handle the i8 case on x86-32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55078 91177308-0d34-0410-b5e6-96231b3b80d8
builtins on X86.
Change "lock" instructions to be on a separate line.
This is needed to work around a bug in the Darwin
assembler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54999 91177308-0d34-0410-b5e6-96231b3b80d8
subreg form on x86-64, to avoid the problem with x86-32
having GPRs that don't have 8-bit subregs.
Also, change several 16-bit instructions to use
equivalent 32-bit instructions. These have a smaller
encoding and avoid partial-register updates.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54223 91177308-0d34-0410-b5e6-96231b3b80d8
which is represented in codegen as an 'and' operation. This matches them
with movz instructions, instead of leaving them to be matched by and
instructions with an immediate field.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54147 91177308-0d34-0410-b5e6-96231b3b80d8
Added abstract class MemSDNode for any Node that have an associated MemOperand
Changed atomic.lcs => atomic.cmp.swap, atomic.las => atomic.load.add, and
atomic.lss => atomic.load.sub
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52706 91177308-0d34-0410-b5e6-96231b3b80d8
index for the input pattern in terms of the output pattern. Instead
keep track of how many fixed operands the input pattern actually
has, and have the input matching code pass the output-emitting
function that index value. This simplifies the code, disentangles
variables_ops from the support for predication operations, and
makes variable_ops more robust.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51808 91177308-0d34-0410-b5e6-96231b3b80d8
cases due to an isel deficiency already noted in
lib/Target/X86/README.txt, but they can be matched in this fold-call.ll
testcase, for example.
This is interesting mainly because it exposes a tricky tblgen bug;
tblgen was incorrectly computing the starting index for variable_ops
in the case of a complex pattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51706 91177308-0d34-0410-b5e6-96231b3b80d8
definitions. This adds a new construct, "discard", for indicating
that a named node in the input matching pattern is to be discarded,
instead of corresponding to a node in the output pattern. This
allows tblgen to know where the arguments for the varaible_ops are
supposed to begin.
This fixes "rdar://5791600", whatever that is ;-).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51699 91177308-0d34-0410-b5e6-96231b3b80d8
Move platform independent code (lowering of possibly overwritten
arguments, check for tail call optimization eligibility) from
target X86ISelectionLowering.cpp to TargetLowering.h and
SelectionDAGISel.cpp.
Initial PowerPC tail call implementation:
Support ppc32 implemented and tested (passes my tests and
test-suite llvm-test).
Support ppc64 implemented and half tested (passes my tests).
On ppc tail call optimization is performed if
caller and callee are fastcc
call is a tail call (in tail call position, call followed by ret)
no variable argument lists or byval arguments
option -tailcallopt is enabled
Supported:
* non pic tail calls on linux/darwin
* module-local tail calls on linux(PIC/GOT)/darwin(PIC)
* inter-module tail calls on darwin(PIC)
If constraints are not met a normal call will be emitted.
A test checking the argument lowering behaviour on x86-64 was added.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50477 91177308-0d34-0410-b5e6-96231b3b80d8
Note: the coalescer will have to be careful about this too, when it starts coalescing insert_subreg nodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48329 91177308-0d34-0410-b5e6-96231b3b80d8
RET instruction instead of using FpSET_ST0_32. This also generalizes
the code to handling returning of multiple FP results.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48209 91177308-0d34-0410-b5e6-96231b3b80d8
Change insert/extract subreg instructions to be able to be used in TableGen patterns.
Use the above features to reimplement an x86-64 pseudo instruction as a pattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48130 91177308-0d34-0410-b5e6-96231b3b80d8
precision integers. This won't actually work
(and most of the code is dead) unless the new
legalization machinery is turned on. While
there, I rationalized the handling of i1, and
removed some bogus (and unused) sextload patterns.
For i1, this could result in microscopically
better code for some architectures (not X86).
It might also result in worse code if annotating
with AssertZExt nodes turns out to be more harmful
than helpful.
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1. Legalize now always promotes truncstore of i1 to i8.
2. Remove patterns and gunk related to truncstore i1 from targets.
3. Rename the StoreXAction stuff to TruncStoreAction in TLI.
4. Make the TLI TruncStoreAction table a 2d table to handle from/to conversions.
5. Mark a wide variety of invalid truncstores as such in various targets, e.g.
X86 currently doesn't support truncstore of any of its integer types.
6. Add legalize support for truncstores with invalid value input types.
7. Add a dag combine transform to turn store(truncate) into truncstore when
safe.
The later allows us to compile CodeGen/X86/storetrunc-fp.ll to:
_foo:
fldt 20(%esp)
fldt 4(%esp)
faddp %st(1)
movl 36(%esp), %eax
fstps (%eax)
ret
instead of:
_foo:
subl $4, %esp
fldt 24(%esp)
fldt 8(%esp)
faddp %st(1)
fstps (%esp)
movl 40(%esp), %eax
movss (%esp), %xmm0
movss %xmm0, (%eax)
addl $4, %esp
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46140 91177308-0d34-0410-b5e6-96231b3b80d8
x86 backend where instructions were not marked maystore/mayload, and perf issues where
instructions were not marked neverHasSideEffects. It would be really nice if we could
write patterns for copy instructions.
I have audited all the x86 instructions down to MOVDQAmr. The flags on others and on
other targets are probably not right in all cases, but no clients currently use this
info that are enabled by default.
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based what flag to set on whether it was already marked as
"isRematerializable". If there was a further check to determine if it's "really"
rematerializable, then I marked it as "mayHaveSideEffects" and created a check
in the X86 back-end similar to the remat one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45132 91177308-0d34-0410-b5e6-96231b3b80d8
adjustment fields, and an optional flag. If there is a "dynamic_stackalloc" in
the code, make sure that it's bracketed by CALLSEQ_START and CALLSEQ_END. If
not, then there is the potential for the stack to be changed while the stack's
being used by another instruction (like a call).
This can only result in tears...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44037 91177308-0d34-0410-b5e6-96231b3b80d8
Turn a store folding instruction into a load folding instruction. e.g.
xorl %edi, %eax
movl %eax, -32(%ebp)
movl -36(%ebp), %eax
orl %eax, -32(%ebp)
=>
xorl %edi, %eax
orl -36(%ebp), %eax
mov %eax, -32(%ebp)
This enables the unfolding optimization for a subsequent instruction which will
also eliminate the newly introduced store instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43192 91177308-0d34-0410-b5e6-96231b3b80d8
for fastcc from X86CallingConv.td. This means that nested functions
are not supported for calling convention 'fastcc'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42934 91177308-0d34-0410-b5e6-96231b3b80d8
enabled by passing -tailcallopt to llc. The optimization is
performed if the following conditions are satisfied:
* caller/callee are fastcc
* elf/pic is disabled OR
elf/pic enabled + callee is in module + callee has
visibility protected or hidden
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42870 91177308-0d34-0410-b5e6-96231b3b80d8
keep f32 in SSE registers and f64 in x87. This
is effectively a new codegen mode.
Change addLegalFPImmediate to permit float and
double variants to do different things.
Adjust callers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42246 91177308-0d34-0410-b5e6-96231b3b80d8
mnemonics from their operands instead of single spaces. This makes the
assembly output a little more consistent with various other compilers
(f.e. GCC), and slightly easier to read. Also, update the regression
tests accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40648 91177308-0d34-0410-b5e6-96231b3b80d8
This patch fills the last necessary bits to enable exceptions
handling in LLVM. Currently only on x86-32/linux.
In fact, this patch adds necessary intrinsics (and their lowering) which
represent really weird target-specific gcc builtins used inside unwinder.
After corresponding llvm-gcc patch will land (easy) exceptions should be
more or less workable. However, exceptions handling support should not be
thought as 'finished': I expect many small and not so small glitches
everywhere.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39855 91177308-0d34-0410-b5e6-96231b3b80d8
instruction flag, and use the flag along with a virtual member function
hook for targets to override if there are instructions that are only
trivially rematerializable with specific operands (i.e. constant pool
loads).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37728 91177308-0d34-0410-b5e6-96231b3b80d8
with a general target hook to identify rematerializable instructions. Some
instructions are only rematerializable with specific operands, such as loads
from constant pools, while others are always rematerializable. This hook
allows both to be identified as being rematerializable with the same
mechanism.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37644 91177308-0d34-0410-b5e6-96231b3b80d8
Also, fixed static case in presence of eax livin. This fixes PR331
PS: Why don't we still have push/pop instructions? :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36195 91177308-0d34-0410-b5e6-96231b3b80d8
- Proper support for both small static and PIC modes under X86-64
- Some (non-optimal) support for medium modes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32046 91177308-0d34-0410-b5e6-96231b3b80d8
using test, which provides nice simplifications like:
- movl %edi, %ecx
- andl $2, %ecx
- cmpl $0, %ecx
+ testl $2, %edi
je LBB1_11 #cond_next90
There are a couple of dagiselemitter deficiencies that this exposes, they will
be handled later.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30156 91177308-0d34-0410-b5e6-96231b3b80d8
Fold c2 in (x << c1) | c2 where (c2 < c1)
e.g.
int test(int x) {
return (x << 3) + 7;
}
This can be codegen'd as:
leal 7(,%eax,8), %eax
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28550 91177308-0d34-0410-b5e6-96231b3b80d8
- Fix a couple of minor bugs in i16immSExt8 and i16immZExt8.
- Added loadiPTR fragment used for indirect jumps and calls.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28392 91177308-0d34-0410-b5e6-96231b3b80d8
movw. That is we promote the destination operand to r16. So
%CH = TRUNC_R16_R8 %BP
is emitted as
movw %bp, %cx.
This is incorrect. If %cl is live, it would be clobbered.
Ideally we want to do the opposite, that is emitted it as
movb ??, %ch
But this is not possible since %bp does not have a r8 sub-register.
We are now defining a new register class R16_ which is a subclass of R16
containing only those 16-bit registers that have r8 sub-registers (i.e.
AX - DX). We isel the truncate to two instructions, a MOV16to16_ to copy the
value to the R16_ class, followed by a TRUNC_R16_R8.
Due to bug 770, the register colaescer is not going to coalesce between R16 and
R16_. That will be fixed later so we can eliminate the MOV16to16_. Right now, it
can only be eliminated if we are lucky that source and destination registers are
the same.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28164 91177308-0d34-0410-b5e6-96231b3b80d8
that gets emitted as movl (for r32 to i16, i8) or a movw (for r16 to i8). And
if the destination gets allocated a subregister of the source operand, then
the instruction will not be emitted at all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28119 91177308-0d34-0410-b5e6-96231b3b80d8
x86 and ppc for 100% dense switch statements when relocations are non-PIC.
This support will be extended and enhanced in the coming days to support
PIC, and less dense forms of jump tables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27947 91177308-0d34-0410-b5e6-96231b3b80d8
* Add patterns to handle GlobalAddress, ConstantPool, etc.
MOV32ri to materialize these nodes in registers.
ADD32ri to handle %reg + GA, etc.
MOV32mi to handle store GA, etc. to memory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26374 91177308-0d34-0410-b5e6-96231b3b80d8
and ExternalSymbol.
- Use C++ code (rather than tblgen'd selection code) to match the above
mentioned leaf nodes. Do not mutate and nodes and do not record the
selection in CodeGenMap. These nodes should be safe to duplicate. This is
a performance win.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26335 91177308-0d34-0410-b5e6-96231b3b80d8
1. Various asm printer bug.
2. Lowering bug. Now TargetGlobalAddress is wrapped in X86ISD::TGAWrapper.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26324 91177308-0d34-0410-b5e6-96231b3b80d8
and SUBE nodes that actually expose what's going on and allow for
significant simplifications in the targets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26255 91177308-0d34-0410-b5e6-96231b3b80d8
proves to be worth 20% on Ptrdist/ks. Might be related to dependency
breaking support.
2. Added FsMOVAPSrr and FsMOVAPDrr as aliases to MOVAPSrr and MOVAPDrr. These
are used for FR32 / FR64 reg-to-reg copies.
3. Tell reg-allocator to generate MOVSSrm / MOVSDrm and MOVSSmr / MOVSDmr to
spill / restore FsMOVAPSrr and FsMOVAPDrr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26241 91177308-0d34-0410-b5e6-96231b3b80d8
- Added a new format for instructions where the source register is implied
and it is same as the destination register. Used for pseudo instructions
that clear the destination register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25872 91177308-0d34-0410-b5e6-96231b3b80d8
* Allow a register node as SelectAddr() base.
* ExternalSymbol -> TargetExternalSymbol as direct function callee.
* Use X86::ESP register rather than CopyFromReg(X86::ESP) as stack ptr for
call parmater passing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25207 91177308-0d34-0410-b5e6-96231b3b80d8
Currently tblgen cannot tell which operands in the operand list are results so
it assumes the first one is a result. This is bad. Ideally we would fix this
by separating results from inputs, e.g. (res R32:$dst),
(ops R32:$src1, R32:$src2). But that's a more distruptive change. Adding
'let noResults = 1' is the workaround to tell tblgen that the instruction does
not produces a result. It works for now since tblgen does not support
instructions which produce multiple results.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25017 91177308-0d34-0410-b5e6-96231b3b80d8
* Added a pseudo instruction (for each target) that represent "return void".
This is a workaround for lack of optional flag operand (return void is not
lowered so it does not have a flag operand.)
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that were overloaded to work before and after the stackifier runs. With the
new clean world, it is possible to write patterns for these instructions: woo!
This also adds a few simple patterns here and there, though there are a lot
still missing. These should be easy to add though. :)
See the comments under "Floating Point Stack Support" for more details on
the new world order.
This patch as absolutely no effect on the generated code, woo!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24899 91177308-0d34-0410-b5e6-96231b3b80d8
for Darwin.
* Added lowering hook for ISD::RET. It inserts CopyToRegs for the return
value (or store / fld / copy to ST(0) for floating point value). This
eliminate the need to write C++ code to handle RET with variable number
of operands.
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false if the match is not profitable. e.g. leal 1(%eax), %eax.
* Added patterns for X86 integer loads and LEA32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24635 91177308-0d34-0410-b5e6-96231b3b80d8
1. Remove redundant type casts now that PR673 is implemented.
2. Implement the OUT*ir instructions correctly. The port number really
*is* a 16-bit value, but the patterns should only match if the number
is 0-255. Update the patterns so they now match.
3. Fix patterns for shifts to reflect that the shift amount is always an
i8, not an i16 as they were believed to be before. This previous fib
stopped working when we started knowing that CL has type i8.
4. Change use of i16i8imm in SH*ri patterns to all be imm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24599 91177308-0d34-0410-b5e6-96231b3b80d8
Give a whole bunch of other stuff variable operands, particularly FP. The
FP stackifier is playing fast and loose with operands here, so we have to
mark them all as variable. This will have to be fixed before we can dag->dag
the X86 backend. The solution is for the pre-stackifier and post-stackifier
instructions to all be disjoint.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22890 91177308-0d34-0410-b5e6-96231b3b80d8
XMM registers. There are many known deficiencies and fixmes, which will be
addressed ASAP. The major benefit of this work is that it will allow the
LLVM register allocator to allocate FP registers across basic blocks.
The x86 backend will still default to x87 style FP. To enable this work,
you must pass -enable-sse-scalar-fp and either -sse2 or -sse3 to llc.
An example before and after would be for:
double foo(double *P) { double Sum = 0; int i; for (i = 0; i < 1000; ++i)
Sum += P[i]; return Sum; }
The inner loop looks like the following:
x87:
.LBB_foo_1: # no_exit
fldl (%esp)
faddl (%eax,%ecx,8)
fstpl (%esp)
incl %ecx
cmpl $1000, %ecx
#FP_REG_KILL
jne .LBB_foo_1 # no_exit
SSE2:
addsd (%eax,%ecx,8), %xmm0
incl %ecx
cmpl $1000, %ecx
#FP_REG_KILL
jne .LBB_foo_1 # no_exit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22340 91177308-0d34-0410-b5e6-96231b3b80d8
working. The instruction selector changes will hopefully be coming later
this week once they are debugged. This is necessary to support the darwin
x86 FP model, and is recommended by intel as the replacement for x87. As
a bonus, the register allocator knows how to deal with these registers
across basic blocks, unliky the FP stackifier. This leads to significantly
better codegen in several cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22300 91177308-0d34-0410-b5e6-96231b3b80d8
