(OP (trunc x), (trunc y)) -> (trunc (OP x, y))
Unfortunately this simple change causes dag combine to infinite looping. The problem is the shrink demanded ops optimization tend to canonicalize expressions in the opposite manner. That is badness. This patch disable those optimizations in dag combine but instead it is done as a late pass in sdisel.
This also exposes some deficiencies in dag combine and x86 setcc / brcond lowering. Teach them to look pass ISD::TRUNCATE in various places.
llvm-svn: 92849
return partial registers. This affected the back-end lowering code some.
Also patch up some places I missed before in the "get" functions.
llvm-svn: 91880
bunch of associated comments, because it doesn't have anything to do
with DAGs or scheduling. This is another step in decoupling MachineInstr
emitting from scheduling.
llvm-svn: 85517
encodings.
- Make some of the values emitted by the FDEs dependent upon the pointer
size. This is in line with how GCC does things. And it has the benefit of
working for Darwin in 64-bit mode now.
llvm-svn: 80428
support unaligned mem access only for certain types. (Should it be size
instead?)
ARM v7 supports unaligned access for i16 and i32, some v6 variants support it
as well.
llvm-svn: 79127
libcall. Take advantage of this in the ARM backend to rectify broken
choice of CC when hard float is in effect. PIC16 may want to see if
it could be of use in MakePIC16Libcall, which works unchanged.
Patch by Sandeep!
llvm-svn: 79033
Instead of awkwardly encoding calling-convention information with ISD::CALL,
ISD::FORMAL_ARGUMENTS, ISD::RET, and ISD::ARG_FLAGS nodes, TargetLowering
provides three virtual functions for targets to override:
LowerFormalArguments, LowerCall, and LowerRet, which replace the custom
lowering done on the special nodes. They provide the same information, but
in a more immediately usable format.
This also reworks much of the target-independent tail call logic. The
decision of whether or not to perform a tail call is now cleanly split
between target-independent portions, and the target dependent portion
in IsEligibleForTailCallOptimization.
This also synchronizes all in-tree targets, to help enable future
refactoring and feature work.
llvm-svn: 78142
it is highly specific to the object file that will be generated in the end,
this introduces a new TargetLoweringObjectFile interface that is implemented
for each of ELF/MachO/COFF/Alpha/PIC16 and XCore.
Though still is still a brutal and ugly refactoring, this is a major step
towards goodness.
This patch also:
1. fixes a bunch of dangling pointer problems in the PIC16 backend.
2. disables the TargetLowering copy ctor which PIC16 was accidentally using.
3. gets us closer to xcore having its own crazy target section flags and
pic16 not having to shadow sections with its own objects.
4. fixes wierdness where ELF targets would set CStringSection but not
CStringSection_. Factor the code better.
5. fixes some bugs in string lowering on ELF targets.
llvm-svn: 77294
be useful, and it's currently unused. (Some issues: it isn't actually
rich enough to capture the semantics on many architectures, and
semantics can vary depending on the type being shifted.)
llvm-svn: 76633
With the SVR4 ABI on PowerPC, vector arguments for vararg calls are passed differently depending on whether they are a fixed or a variable argument. Variable vector arguments always go into memory, fixed vector arguments are put
into vector registers. If there are no free vector registers available, fixed vector arguments are put on the stack.
The NumFixedArgs attribute allows to decide for an argument in a vararg call whether it belongs to the fixed or variable portion of the parameter list.
llvm-svn: 74764
have the alignment be calculated up front, and have the back-ends obey whatever
alignment is decided upon.
This allows for future work that would allow for precise no-op placement and the
like.
llvm-svn: 74564
The OpActions array had a limit of 32 value types, so change it to use
MVT::MAX_ALLOWED_VALUETYPE in its declaration and change the accesses to
this array to work with a VT.getSimpleVT() that is larger than 32.
Also, add a comment to the place where MVT::MAX_ALLOWED_VALUETYPE is
defined indicating that it must be a multiple of 32.
This is part of the work allow MVT::LAST_VALUETYPE be greater than 32.
llvm-svn: 74130
This change doubles the allowable value for MVT::LAST_VALUETYPE. It does
this by doing several things.
1. Introduces MVT::MAX_ALLOWED_LAST_VALUETYPE which in this change has a
value of 64. This value contains the current maximum for the
MVT::LAST_VALUETYPE.
2. Instead of checking "MVT::LAST_VALUETYPE <= 32", all of those uses
now become "MVT::LAST_VALUETYPE <= MVT::MAX_ALLOWED_LAST_VALUETYPE"
3. Changes the dimension of the ValueTypeActions from 2 elements to four
elements and adds comments ahead of the declaration indicating the it is
"(MVT::MAX_ALLOWED_LAST_VALUETYPE/32) * 2". This at least lets us find
what is affected if and when MVT::MAX_ALLOWED_LAST_VALUETYPE gets
changed.
4. Adds initializers for the new elements of ValueTypeActions.
This does NOT add any types in MVT. That would be done separately.
This doubles the size of ValueTypeActions from 64 bits to 128 bits and
gives us the freedom to add more types for AVX.
llvm-svn: 74110
This changes the IndexedModeAction representation to remove the
limitation on the number of value types in MVT. This limitation
prevents us from specifying AVX types.
Prior to this change IndexedModActions was represented as follows...
uint64_t IndexedModeActions[2][ISD::LAST_INDEXED_MODE];
the first dimension was used to represent loads, then stores. This
imposed a limitation of 32 on the number of value types that could be
handled with this method. The value type was used to shift the two bits
into and out of the approprate bits in the uint64_t.
With this change the array is now represented as ...
uint8_t IndexedModeActions[MVT::LAST_VALUETYPE][2][ISD::LAST_INDEXED_MODE];
Takes more space but removes the limitation on MVT::LAST_VALUETYPE. The
first dimension is now the value_type for the reference. The second
dimension is the load [0] vs. store[1]. The third dimension represents
the various modes for load store. Accesses are now direct, no shifting
or masking.
There are other limitations that need to be removed, so that
MVT::LAST_VALUETYPE can be greater than 32. This is merely the first
step towards that goal.
llvm-svn: 73104
This changes the IndexedModeAction representation to remove the
limitation on the number of value types in MVT. This limitation
prevents us from specifying AVX types.
Prior to this change IndexedModActions was represented as follows...
uint64_t IndexedModeActions[2][ISD::LAST_INDEXED_MODE];
the first dimension was used to represent loads, then stores. This
imposed a limitation of 32 on the number of value types that could be
handled with this method. The value type was used to shift the two bits
into and out of the approprate bits in the uint64_t.
With this change the array is now represented as ...
uint8_t IndexedModeActions[MVT::LAST_VALUETYPE][2][ISD::LAST_INDEXED_MODE];
Takes more space but removes the limitation on MVT::LAST_VALUETYPE. The
first dimension is now the value_type for the reference. The second
dimension is the load [0] vs. store[1]. The third dimension represents
the various modes for load store. Accesses are now direct, no shifting
or masking.
There are other limitations that need to be removed, so that
MVT::LAST_VALUETYPE can be greater than 32. This is merely the first
step towards that goal.
llvm-svn: 73102
Update code generator to use this attribute and remove NoImplicitFloat target option.
Update llc to set this attribute when -no-implicit-float command line option is used.
llvm-svn: 72959
build vectors with i64 elements will only appear on 32b x86 before legalize.
Since vector widening occurs during legalize, and produces i64 build_vector
elements, the dag combiner is never run on these before legalize splits them
into 32b elements.
Teach the build_vector dag combine in x86 back end to recognize consecutive
loads producing the low part of the vector.
Convert the two uses of TLI's consecutive load recognizer to pass LoadSDNodes
since that was required implicitly.
Add a testcase for the transform.
Old:
subl $28, %esp
movl 32(%esp), %eax
movl 4(%eax), %ecx
movl %ecx, 4(%esp)
movl (%eax), %eax
movl %eax, (%esp)
movaps (%esp), %xmm0
pmovzxwd %xmm0, %xmm0
movl 36(%esp), %eax
movaps %xmm0, (%eax)
addl $28, %esp
ret
New:
movl 4(%esp), %eax
pmovzxwd (%eax), %xmm0
movl 8(%esp), %eax
movaps %xmm0, (%eax)
ret
llvm-svn: 72957
e.g.
orl $65536, 8(%rax)
=>
orb $1, 10(%rax)
Since narrowing is not always a win, e.g. i32 -> i16 is a loss on x86, dag combiner consults with the target before performing the optimization.
llvm-svn: 72507
