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
- return attributes - inreg, zext and sext
- parameter attributes
- function attributes - nounwind, readonly, readnone, noreturn
Return attributes use 0 as the index.
Function attributes use ~0U as the index.
This patch requires corresponding changes in llvm-gcc and clang.
llvm-svn: 56704
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
Duncan Sands