on any current target and aren't optimized in DAGCombiner. Instead
of using intermediate nodes, expand the operations, choosing between
simple loads/stores, target-specific code, and library calls,
immediately.
Previously, the code to emit optimized code for these operations
was only used at initial SelectionDAG construction time; now it is
used at all times. This fixes some cases where rep;movs was being
used for small copies where simple loads/stores would be better.
This also cleans up code that checks for alignments less than 4;
let the targets make that decision instead of doing it in
target-independent code. This allows x86 to use rep;movs in
low-alignment cases.
Also, this fixes a bug that resulted in the use of rep;stos for
memsets of 0 with non-constant memory size when the alignment was
at least 4. It's better to use the library in this case, which
can be significantly faster when the size is large.
This also preserves more SourceValue information when memory
intrinsics are lowered into simple loads/stores.
llvm-svn: 49572
For x86, if sse2 is available, it's not a good idea since cvtss2sd is slower than a movsd load and it prevents load folding. On x87, it's important to shrink fp constant since fldt is very expensive.
llvm-svn: 47931
calls. Before arguments that could overwrite each other were
explicitly lowered to a stack slot, not giving the register allocator
a chance to optimize. Now a sequence of copyto/copyfrom virtual
registers ensures that arguments are loaded in (virtual) registers
before they are lowered to the stack slot (and might overwrite each
other). Also parameter stack slots are marked mutable for
(potentially) tail calling functions.
llvm-svn: 47593
unifying the copied algorithms and saving over 500 LOC. There should
be no functionality change, but please test on your favorite x86
target.
llvm-svn: 45627
1) Change the interface to TargetLowering::ExpandOperationResult to
take and return entire NODES that need a result expanded, not just
the value. This allows us to handle things like READCYCLECOUNTER,
which returns two values.
2) Implement (extremely limited) support in LegalizeDAG::ExpandOp for MERGE_VALUES.
3) Reimplement custom lowering in LegalizeDAGTypes in terms of the new
ExpandOperationResult. This makes the result simpler and fully
general.
4) Implement (fully general) expand support for MERGE_VALUES in LegalizeDAGTypes.
5) Implement ExpandOperationResult support for ARM f64->i64 bitconvert and ARM
i64 shifts, allowing them to work with LegalizeDAGTypes.
6) Implement ExpandOperationResult support for X86 READCYCLECOUNTER and FP_TO_SINT,
allowing them to work with LegalizeDAGTypes.
LegalizeDAGTypes now passes several more X86 codegen tests when enabled and when
type legalization in LegalizeDAG is ifdef'd out.
llvm-svn: 44300
transformation. Previously, it's restricted by ensuring the number of load uses
is one. Now the restriction is loosened up by allowing setcc uses to be
"extended" (e.g. setcc x, c, eq -> setcc sext(x), sext(c), eq).
llvm-svn: 43465
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
llvm-svn: 42870
use ISD::{S,U}DIVREM and ISD::{S,U}MUL_HIO. Move the lowering code
associated with these operators into target-independent in LegalizeDAG.cpp
and TargetLowering.cpp.
llvm-svn: 42762
The only generated code difference is that now we call memcpy when
the size of the array is unknown. This matches GCC behavior and is
better since the run time value can be arbitrarily large.
llvm-svn: 42433
both results with a single div or idiv instruction. This uses new X86ISD
nodes for DIV and IDIV which are introduced during the legalize phase
so that the SelectionDAG's CSE can automatically eliminate redundant
computations.
llvm-svn: 42308
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.
llvm-svn: 42246
Make the alignedload and alignedstore patterns always require 16-byte
alignment. This way when they are used in the "Fs" instructions, in which
a vector instruction is used for a scalar purpose, they can still require
the full vector alignment. And add a regression test for this.
llvm-svn: 40555
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.
llvm-svn: 39855
in addition to the intrinsic forms. Add spill-folding entries for these new
instructions, and for the scalar min and max instrinsic instructions which
were missing. And add some preliminary ISelLowering code for using the new
non-intrinsic vector sqrt instruction, and fneg and fabs.
llvm-svn: 38478
TargetLowering to SelectionDAG so that they have more convenient
access to the current DAG, in preparation for the ValueType routines
being changed from standalone functions to members of SelectionDAG for
the pre-legalize vector type changes.
llvm-svn: 37704
vector_shuffle v1, v2, <2, 6, 3, 7>
I.e.
vector_shuffle v, undef, <2, 2, 3, 3>
MMX only has a shuffle for v4i16 vectors. It needs to use the unpackh for
this type of operation.
llvm-svn: 36403
function. This function now uses GetRetValueLocs to determine *where*
the result values are located and concerns itself with *how* to pull the
values out.
llvm-svn: 34586
registers out from the logic of *how* to return them.
This changes X86-64 to mark EAX live out when returning a 32-bit value,
where before it marked RAX liveout.
llvm-svn: 34582
1. New parameter attribute called 'inreg'. It has meaning "place this
parameter in registers, if possible". This is some generalization of
gcc's regparm(n) attribute. It's currently used only in X86-32 backend.
2. Completely rewritten CC handling/lowering code inside X86 backend.
Merged stdcall + c CCs and fastcall + fast CC.
3. Dropped CSRET CC. We cannot add struct return variant for each
target-specific CC (e.g. stdcall + csretcc and so on).
4. Instead of CSRET CC introduced 'sret' parameter attribute. Setting in
on first attribute has meaning 'This is hidden pointer to structure
return. Handle it gently'.
5. Fixed small bug in llvm-extract + add new feature to
FunctionExtraction pass, which relinks all internal-linkaged callees
from deleted function to external linkage. This will allow further
linking everything together.
NOTEs: 1. Documentation will be updated soon.
2. llvm-upgrade should be improved to translate csret => sret.
Before this, there will be some unexpected test fails.
llvm-svn: 33597
or'ing in the sign bit of operand 1.
- Tweaking: rather than left shift the sign bit, fp_extend operand 1 first
before taking its sign bit if its type is smaller than that of operand 0.
llvm-svn: 32932
take v4f32 / v2f64 operands and may end up causing larger spills / restores.
Added X86 specific nodes X86ISD::FMAX, X86ISD::FMIN instead.
This fixes PR996.
llvm-svn: 31645
shuffle v, undef, <2, ?, 3, ?>
to movhlps
It should match to unpckhps instead.
Added proper matching code for
shuffle v, undef, <2, 3, 2, 3>
llvm-svn: 31519
The CFE refers to all single-register constraints (like "A") by their 16-bit
name, even though the 8 or 32-bit version of the register may be needed.
The X86 backend should realize what is going on and redecode the name back
to its proper form.
llvm-svn: 29420
Dan Gohman