files. First, add a new block USELIST_BLOCK to the bitcode format. This is
where USELIST_CODE_ENTRYs will be stored. The format of the USELIST_CODE_ENTRYs
have not yet been defined. Add support in the BitcodeReader for parsing the
USELIST_BLOCK.
Part of rdar://9860654 and PR5680.
llvm-svn: 146078
This implements the 'landingpad' instruction. It's used to indicate that a basic
block is a landing pad. There are several restrictions on its use (see
LangRef.html for more detail). These restrictions allow the exception handling
code to gather the information it needs in a much more sane way.
This patch has the definition, implementation, C interface, parsing, and bitcode
support in it.
llvm-svn: 137501
This adds the 'resume' instruction class, IR parsing, and bitcode reading and
writing. The 'resume' instruction resumes propagation of an existing (in-flight)
exception whose unwinding was interrupted with a 'landingpad' instruction (to be
added later).
llvm-svn: 136589
'atomicrmw' instructions, which allow representing all the current atomic
rmw intrinsics.
The allowed operands for these instructions are heavily restricted at the
moment; we can probably loosen it a bit, but supporting general
first-class types (where it makes sense) might get a bit complicated,
given how SelectionDAG works.
As an initial cut, these operations do not support specifying an alignment,
but it would be possible to add if we think it's useful. Specifying an
alignment lower than the natural alignment would be essentially
impossible to support on anything other than x86, but specifying a greater
alignment would be possible. I can't think of any useful optimizations which
would use that information, but maybe someone else has ideas.
Optimizer/codegen support coming soon.
llvm-svn: 136404
patch brings numerous advantages to LLVM. One way to look at it
is through diffstat:
109 files changed, 3005 insertions(+), 5906 deletions(-)
Removing almost 3K lines of code is a good thing. Other advantages
include:
1. Value::getType() is a simple load that can be CSE'd, not a mutating
union-find operation.
2. Types a uniqued and never move once created, defining away PATypeHolder.
3. Structs can be "named" now, and their name is part of the identity that
uniques them. This means that the compiler doesn't merge them structurally
which makes the IR much less confusing.
4. Now that there is no way to get a cycle in a type graph without a named
struct type, "upreferences" go away.
5. Type refinement is completely gone, which should make LTO much MUCH faster
in some common cases with C++ code.
6. Types are now generally immutable, so we can use "Type *" instead
"const Type *" everywhere.
Downsides of this patch are that it removes some functions from the C API,
so people using those will have to upgrade to (not yet added) new API.
"LLVM 3.0" is the right time to do this.
There are still some cleanups pending after this, this patch is large enough
as-is.
llvm-svn: 134829
Change various bits of code to make better use of the existing PHINode
API, to insulate them from forthcoming changes in how PHINodes store
their operands.
llvm-svn: 133434
--- Reverse-merging r129235 into '.':
D test/Feature/bb_attrs.ll
U include/llvm/BasicBlock.h
U include/llvm/Bitcode/LLVMBitCodes.h
U lib/VMCore/AsmWriter.cpp
U lib/VMCore/BasicBlock.cpp
U lib/AsmParser/LLParser.cpp
U lib/AsmParser/LLLexer.cpp
U lib/AsmParser/LLToken.h
U lib/Bitcode/Reader/BitcodeReader.cpp
U lib/Bitcode/Writer/BitcodeWriter.cpp
llvm-svn: 129259
* Add a "landing pad" attribute to the BasicBlock.
* Modify the bitcode reader and writer to handle said attribute.
Later: The verifier will ensure that the landing pad attribute is used in the
appropriate manner. I.e., not applied to the entry block, and applied only to
basic blocks that are branched to via a `dispatch' instruction.
(This is a work-in-progress.)
llvm-svn: 129235
Add a unnamed_addr bit to global variables and functions. This will be used
to indicate that the address is not significant and therefore the constant
or function can be merged with others.
If an optimization pass can show that an address is not used, it can set this.
Examples of things that can have this set by the FE are globals created to
hold string literals and C++ constructors.
Adding unnamed_addr to a non-const global should have no effect unless
an optimization can transform that global into a constant.
Aliases are not allowed to have unnamed_addr since I couldn't figure
out any use for it.
llvm-svn: 123063
is different from what the code now uses in a two ways: NamedMDNodes
were considered Values and included in the numbering, and the
function-local metadata counter wasn't reset between functions.
The later problem breaks lazy deserialization, so instead of trying
to emulate the old numbering, just drop the old metadata. The only
in-tree use case is debug info with LTO, where the QOI loss is
considered acceptable.
llvm-svn: 113557
It's similar to "linker_private_weak", but it's known that the address of the
object is not taken. For instance, functions that had an inline definition, but
the compiler decided not to inline it. Note, unlike linker_private and
linker_private_weak, linker_private_weak_def_auto may have only default
visibility. The symbols are removed by the linker from the final linked image
(executable or dynamic library).
llvm-svn: 111684
Make MDNode::destroy private.
Fix the one thing that used MDNode::destroy, outside of MDNode itself.
One should never delete or destroy an MDNode explicitly. MDNodes
implicitly go away when there are no references to them (implementation
details aside).
llvm-svn: 109028
bitcode file, so that two bitcode files where the same metadata kind
name happens to have been assigned a different ID can still be
linked together.
Eliminate the restriction that metadata kind IDs can't be 0.
Change MD_dbg from 1 to 0, because we can now, and because it's
less mysterious that way.
llvm-svn: 108939
Objective-C metadata types which should be marked as "weak", but which the
linker will remove upon final linkage. However, this linkage isn't specific to
Objective-C.
For example, the "objc_msgSend_fixup_alloc" symbol is defined like this:
.globl l_objc_msgSend_fixup_alloc
.weak_definition l_objc_msgSend_fixup_alloc
.section __DATA, __objc_msgrefs, coalesced
.align 3
l_objc_msgSend_fixup_alloc:
.quad _objc_msgSend_fixup
.quad L_OBJC_METH_VAR_NAME_1
This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".
Currently only supported on Darwin platforms.
llvm-svn: 107433
metadata types which should be marked as "weak", but which the linker will
remove upon final linkage. For example, the "objc_msgSend_fixup_alloc" symbol is
defined like this:
.globl l_objc_msgSend_fixup_alloc
.weak_definition l_objc_msgSend_fixup_alloc
.section __DATA, __objc_msgrefs, coalesced
.align 3
l_objc_msgSend_fixup_alloc:
.quad _objc_msgSend_fixup
.quad L_OBJC_METH_VAR_NAME_1
This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".
llvm-svn: 107205
the wrong level. Clients which need to leave the stream open but
which still require the bitcode bits to be on disk should call
flush themselves.
llvm-svn: 104885
with a fix for self-hosting
rotate CallInst operands, i.e. move callee to the back
of the operand array
the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary
llvm-svn: 101465
with a fix
rotate CallInst operands, i.e. move callee to the back
of the operand array
the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary
llvm-svn: 101397
of the operand array
the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary
llvm-svn: 101364
having the bitcode writer materialize mdnodes for all the
debug location tuples when writing out the bc file and
stores the information in a more compact form. For example,
the -O0 -g bc file for combine.c in 176.gcc shrinks from
739392 to 512096 bytes.
This concludes my planned short-term debug info work.
llvm-svn: 100261
I have audited all getOperandNo calls now, fixing
hidden assumptions. CallSite related uglyness will
be eliminated successively.
Note this patch has a long and griveous history,
for all the back-and-forths have a look at
CallSite.h's log.
llvm-svn: 99399
This time I did a self-hosted bootstrap on Linux x86-64,
with no problems. Let's see how darwin 64-bit self-hosting
goes. At the first sign of failure I'll back this out.
Maybe the valgrind bots give me a hint of what may be wrong
(it at all).
llvm-svn: 98957
Modules and ModuleProviders. Because the "ModuleProvider" simply materializes
GlobalValues now, and doesn't provide modules, it's renamed to
"GVMaterializer". Code that used to need a ModuleProvider to materialize
Functions can now materialize the Functions directly. Functions no longer use a
magic linkage to record that they're materializable; they simply ask the
GVMaterializer.
Because the C ABI must never change, we can't remove LLVMModuleProviderRef or
the functions that refer to it. Instead, because Module now exposes the same
functionality ModuleProvider used to, we store a Module* in any
LLVMModuleProviderRef and translate in the wrapper methods. The bindings to
other languages still use the ModuleProvider concept. It would probably be
worth some time to update them to follow the C++ more closely, but I don't
intend to do it.
Fixes http://llvm.org/PR5737 and http://llvm.org/PR5735.
llvm-svn: 94686
getMDKindID/getMDKindNames methods to LLVMContext (and add
convenience methods to Module), eliminating MetadataContext.
Move the state that it maintains out to LLVMContext.
llvm-svn: 92259
I asked Devang to do back on Sep 27. Instead of going through the
MetadataContext class with methods like getMD() and getMDs(), just
ask the instruction directly for its metadata with getMetadata()
and getAllMetadata().
This includes a variety of other fixes and improvements: previously
all Value*'s were bloated because the HasMetadata bit was thrown into
value, adding a 9th bit to a byte. Now this is properly sunk down to
the Instruction class (the only place where it makes sense) and it
will be folded away somewhere soon.
This also fixes some confusion in getMDs and its clients about
whether the returned list is indexed by the MDID or densely packed.
This is now returned sorted and densely packed and the comments make
this clear.
This introduces a number of fixme's which I'll follow up on.
llvm-svn: 92235
block with a blockaddress still referring to it' replace the invalid
blockaddress with a new blockaddress(@func, null) instead of a
inttoptr(1).
This changes the bitcode encoding format, and still needs codegen
support (this should produce a non-zero value, referring to the entry
block of the function would also be quite reasonable).
llvm-svn: 85678
In the new world order, BlockAddress can have a BasicBlock operand.
This doesn't permute much, because if you have a ConstantExpr (or
anything more specific than Constant) we still know the operand has
to be a Constant.
llvm-svn: 85375
the new predicates I added) instead of going through a context and doing a
pointer comparison. Besides being cheaper, this allows a smart compiler
to turn the if sequence into a switch.
llvm-svn: 83297
"private" symbols which the assember shouldn't strip, but which the linker may
remove after evaluation. This is mostly useful for Objective-C metadata.
This is plumbing, so we don't have a use of it yet. More to come, etc.
llvm-svn: 76385
This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").
llvm-svn: 75640
Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.
llvm-svn: 75379
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.
For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.
This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt
llvm-svn: 72897
to support C99 inline, GNU extern inline, etc. Related bugzilla's
include PR3517, PR3100, & PR2933. Nothing uses this yet, but it
appears to work.
llvm-svn: 68940
Constant, MDString and MDNode which can only be used by globals with a name
that starts with "llvm." or as arguments to a function with the same naming
restriction.
llvm-svn: 68420
same as a normal i80 {low64, high16} rather
than its own {high64, low16}. A depressing number
of places know about this; I think I got them all.
Bitcode readers and writers convert back to the old
form to avoid breaking compatibility.
llvm-svn: 67562
changes.
For InvokeInst now all arguments begin at op_begin().
The Callee, Cont and Fail are now faster to get by
access relative to op_end().
This patch introduces some temporary uglyness in CallSite.
Next I'll bring CallInst up to a similar scheme and then
the uglyness will magically vanish.
This patch also exposes all the reliance of the libraries
on InvokeInst's operand ordering. I am thinking of taking
care of that too.
llvm-svn: 66920
and extern_weak_odr. These are the same as the non-odr versions,
except that they indicate that the global will only be overridden
by an *equivalent* global. In C, a function with weak linkage can
be overridden by a function which behaves completely differently.
This means that IP passes have to skip weak functions, since any
deductions made from the function definition might be wrong, since
the definition could be replaced by something completely different
at link time. This is not allowed in C++, thanks to the ODR
(One-Definition-Rule): if a function is replaced by another at
link-time, then the new function must be the same as the original
function. If a language knows that a function or other global can
only be overridden by an equivalent global, it can give it the
weak_odr linkage type, and the optimizers will understand that it
is alright to make deductions based on the function body. The
code generators on the other hand map weak and weak_odr linkage
to the same thing.
llvm-svn: 66339
alignment attribute such that 0 means unaligned.
This will probably require a rebuild of llvm-gcc because of the change to
Attributes.h. If you see many test failures on "make check", please rebuild
your llvm-gcc.
llvm-svn: 61030
callee will not introduce any new aliases of that pointer.
The attributes had all bits allocated already, so I decided to collapse
alignment. Alignment was previously stored as a 16-bit integer from bits 16 to
32 of the attribute, but it was required to be a power of 2. Now it's stored in
log2 encoded form in five bits from 16 to 21. That gives us 11 more bits of
space.
You may have already noticed that you only need four bits to encode a 16-bit
power of two, so why five bits? Because the AsmParser accepted 32-bit
alignments, even though we couldn't store them (they were silently discarded).
Now we can store them in memory, but not in the bitcode.
The bitcode format was already storing these as 64-bit VBR integers. So, the
bitcode format stays the same, keeping the alignment values stored as 16 bit
raw values. There's some hideous code in the reader and writer that deals with
this, waiting to be ripped out the moment we run out of bits again and have to
replace the parameter attributes table encoding.
llvm-svn: 61019
s/ParamAttr/Attribute/g
s/PAList/AttrList/g
s/FnAttributeWithIndex/AttributeWithIndex/g
s/FnAttr/Attribute/g
This sets the stage
- to implement function notes as function attributes and
- to distinguish between function attributes and return value attributes.
This requires corresponding changes in llvm-gcc and clang.
llvm-svn: 56622
bitcode reader/writer as follows:
- add and use new bitcode FUNC_CODE_INST_VSELECT to handle the llvm
select opcode using either i1 or [N x i1] as the selector.
- retain old BITCODE FUNC_CODE_INST_SELECT in the bitcode reader to
handle select on i1 for backwards compatibility with existing bitcode
files.
- re-enable the vector-select.ll test program.
Also, rename the recently added bitcode opcode FUNC_CODE_INST_VCMP to
FUNC_CODE_INST_CMP2 and make the bitcode writer use it to handle
fcmp/icmp on scalars or vectors. In the bitcode writer, use
FUNC_CODE_INST_CMP for vfcmp/vicmp only. In the bitcode reader, have
FUNC_CODE_INST_CMP handle icmp/fcmp returning bool, for backwards
compatibility with existing bitcode files.
Patch by Preston Gurd!
llvm-svn: 56233
and, if so, to return a vector of boolean as a result;
Extend the select LLVM IR instruction to allow you to specify a result
type which is a vector of boolean, in which case the result will be an
element-wise selection instead of choosing one vector or the other; and
Update LangRef.html to describe these changes.
This patch was contributed by Preston Gurd!
llvm-svn: 55969
In particular, Collector was confusing to implementors. Several
thought that this compile-time class was the place to implement
their runtime GC heap. Of course, it doesn't even exist at runtime.
Specifically, the renames are:
Collector -> GCStrategy
CollectorMetadata -> GCFunctionInfo
CollectorModuleMetadata -> GCModuleInfo
CollectorRegistry -> GCRegistry
Function::getCollector -> getGC (setGC, hasGC, clearGC)
Several accessors and nested types have also been renamed to be
consistent. These changes should be obvious.
llvm-svn: 54899
Remove the GetResultInst instruction. It is still accepted in LLVM assembly
and bitcode, where it is now auto-upgraded to ExtractValueInst. Also, remove
support for return instructions with multiple values. These are auto-upgraded
to use InsertValueInst instructions.
The IRBuilder still accepts multiple-value returns, and auto-upgrades them
to InsertValueInst instructions.
llvm-svn: 53941
bc files for modules with a target triple that indicates they are for
darwin. The reader unconditionally handles this, and the writer could
turn this on for more targets if we care.
This change has two benefits for darwin:
1) it allows us to encode the cpu type of the file in an easy to read
place that doesn't require decoding the bc file.
2) it works around a bug (IMO) in darwin's AR where it is incapable of
handling files that are not a multiple of 8 bytes long. BC files
are only guaranteed to be multiples of 4 bytes long.
llvm-svn: 53275
insertvalue and extractvalue to use constant indices instead of
Value* indices. And begin updating LangRef.html.
There's definately more to come here, but I'm checking this
basic support in now to make it available to people who are
interested.
llvm-svn: 51806
and bitcode support for the extractvalue and insertvalue
instructions and constant expressions.
Note that this does not yet include CodeGen support.
llvm-svn: 51468
are represented as "weak", but there are subtle differences
in some cases on Darwin, so we need both. The intent
is that "common" will behave identically to "weak" unless
somebody changes their target to do something else.
No functional change as yet.
llvm-svn: 51118
1. There is now a "PAListPtr" class, which is a smart pointer around
the underlying uniqued parameter attribute list object, and manages
its refcount. It is now impossible to mess up the refcount.
2. PAListPtr is now the main interface to the underlying object, and
the underlying object is now completely opaque.
3. Implementation details like SmallVector and FoldingSet are now no
longer part of the interface.
4. You can create a PAListPtr with an arbitrary sequence of
ParamAttrsWithIndex's, no need to make a SmallVector of a specific
size (you can just use an array or scalar or vector if you wish).
5. All the client code that had to check for a null pointer before
dereferencing the pointer is simplified to just access the
PAListPtr directly.
6. The interfaces for adding attrs to a list and removing them is a
bit simpler.
Phase #2 will rename some stuff (e.g. PAListPtr) and do other less
invasive changes.
llvm-svn: 48289
regions of memory that have a target specific relationship, as described in the
Embedded C Technical Report.
This also implements the 2007-12-11-AddressSpaces test,
which demonstrates how address space attributes can be used in LLVM IR.
In addition, this patch changes the bitcode signature for stores (in a backwards
compatible manner), such that the pointer type, rather than the pointee type, is
encoded. This permits type information in the pointer (e.g. address space) to be
preserved for stores.
LangRef updates are forthcoming.
llvm-svn: 44858
methods are new to Function:
bool hasCollector() const;
const std::string &getCollector() const;
void setCollector(const std::string &);
void clearCollector();
The assembly representation is as such:
define void @f() gc "shadow-stack" { ...
The implementation uses an on-the-side table to map Functions to
collector names, such that there is no overhead. A StringPool is
further used to unique collector names, which are extremely
likely to be unique per process.
llvm-svn: 44769
the function type, instead they belong to functions
and function calls. This is an updated and slightly
corrected version of Reid Spencer's original patch.
The only known problem is that auto-upgrading of
bitcode files doesn't seem to work properly (see
test/Bitcode/AutoUpgradeIntrinsics.ll). Hopefully
a bitcode guru (who might that be? :) ) will fix it.
llvm-svn: 44359
No compile-time support for constant operations yet,
just format transformations. Make readers and
writers work. Split constants into 2 doubles in
Legalize.
llvm-svn: 42865
access to bits). Use them in place of float and
double interfaces where appropriate.
First bits of x86 long double constants handling
(untested, probably does not work).
llvm-svn: 41858
Use APFloat in UpgradeParser and AsmParser.
Change all references to ConstantFP to use the
APFloat interface rather than double. Remove
the ConstantFP double interfaces.
Use APFloat functions for constant folding arithmetic
and comparisons.
(There are still way too many places APFloat is
just a wrapper around host float/double, but we're
getting there.)
llvm-svn: 41747
to handle values bigger than double. If we assume host==target and host
long double works correctly, this is not too bad, but we don't want to
have that limitation longterm. I could implement accepting double
constants as long double or something like that, which would lead to
incorrect codegen with no errors; the more I think about that the worse
it seems. Rather than do such a hack that would be backed out later,
I'm settling for giving reasonable error messages, for now.
llvm-svn: 40974
block from:
Block ID #11 (CONSTANTS_BLOCK):
Num Instances: 1722
Total Size: 3.85976e+06b/482470B/120617W
% of file: 16.7609
Average Size: 2241.44b/280.18B/70.045W
Tot/Avg SubBlocks: 0/0
Tot/Avg Abbrevs: 1/0.00058072
Tot/Avg Records: 26423/15.3444
% Abbrev Recs: 69.1746
to:
Block ID #11 (CONSTANTS_BLOCK):
Num Instances: 1724
Total Size: 2.62406e+06b/328008B/82001.9W
% of file: 12.041
Average Size: 1522.08b/190.26B/47.5649W
Tot/Avg SubBlocks: 0/0
Tot/Avg Abbrevs: 2/0.00116009
Tot/Avg Records: 26280/15.2436
% Abbrev Recs: 68.9992
This shrinks kc++ from 2815788 to 2724088 bytes, which means the bitcode
file is now smaller than the bytecode file.
llvm-svn: 36820
This shrinks the type_block of kc++ from 139901 bits to 99389 bits (0.55% to 0.39%
of the file), a 40% reduction.
This shrink the record from:
Block ID #10 (TYPE_BLOCK):
Num Instances: 1
Total Size: 139901b/17487.6B/4371.91W
% of file: 0.549306
Num Abbrevs: 0
Num Records: 3203
% Abbrev Recs: 0
to:
Block ID #10 (TYPE_BLOCK):
Num Instances: 1
Total Size: 99389b/12423.6B/3105.91W
% of file: 0.390862
Num Abbrevs: 4
Num Records: 3203
% Abbrev Recs: 99.6566
With a common histogram of:
Code Histogram:
1613 POINTER
1100 FUNCTION
255 STRUCT
224 ARRAY
5 INTEGER
2 OPAQUE
1 LABEL
1 DOUBLE
1 VOID
1 NUMENTRY
llvm-svn: 36776
with 6 bits where possible. This shrinks kc++ from 3324164B to 3183584B. The
old VST was:
Block ID #14 (VALUE_SYMTAB):
Total Size: 1.26713e+07b/1.58391e+06B/395978W
Average Size: 5403.53b/675.442B/168.86W
% of file: 47.6484
The new one is:
Block ID #14 (VALUE_SYMTAB):
Total Size: 1.15467e+07b/1.44334e+06B/360834W
Average Size: 4923.96b/615.495B/153.874W
% of file: 45.3368
This is 11% smaller than the VST in the bytecode format.
llvm-svn: 36771
relieves us from having to emit the abbrevs into each instance of the block.
This shrinks kc.bit from 3368K to 3333K, but will be a more significant win
once instructions are abbreviated.
The VST went from:
Block ID #14 (VALUE_SYMTAB):
Num Instances: 2345
Total Size: 1.29508e+07b/1.61885e+06B/404713W
Average Size: 5522.73b/690.342B/172.585W
% of file: 48.0645
Tot/Avg SubBlocks: 0/0
Tot/Avg Abbrevs: 7035/3
Tot/Avg Records: 120924/51.5667
% Abbrev Recs: 100
to:
Block ID #14 (VALUE_SYMTAB):
Num Instances: 2345
Total Size: 1.26713e+07b/1.58391e+06B/395978W
Average Size: 5403.53b/675.442B/168.86W
% of file: 47.5198
Tot/Avg SubBlocks: 0/0
Tot/Avg Abbrevs: 0/0
Tot/Avg Records: 120924/51.5667
% Abbrev Recs: 100
because we didn't emit the same 3 abbrevs 2345 times :)
llvm-svn: 36767
where we can. This shrinks kc++'s down to 3368K, with a VST record of:
Block ID #14 (VALUE_SYMTAB):
Num Instances: 2345
Total Size: 1.29508e+07b/1.61885e+06B/404713W
Average Size: 5522.73b/690.342B/172.585W
% of file: 48.0645
Tot/Avg SubBlocks: 0/0
Tot/Avg Abbrevs: 7035/3
Tot/Avg Records: 120924/51.5667
% Abbrev Recs: 100
Isn't it nice to be able to optimizer bc size without touching the reader? :)
llvm-svn: 36759