the noalias argument on function attributes be usable to model the
C99 restrict keyword on arguments, and to allow AliasAnalysis to
consider a noalias-attributed argument to be an "identified object".
To support this, refactor a new "based on" concept out of the current
pointer aliasing "associated" concept. This "based on" concept is very
similar to (though it is not identical with) the "based on" concept
in C99.
Also, reword the definition of NoAlias to more closely describe the
concept that the optimizer uses.
llvm-svn: 107495
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
NOTE: 2nd part changeset for cfe trunk to follow.
*** PRE-PATCH ISSUES ADDRESSED
- clang api docs fail build from objdir
- clang/llvm api docs collide in install PREFIX/
- clang/llvm main docs collide in install
- clang/llvm main docs have full of hard coded destination
assumptions and make use of absolute root in static html files;
namely CommandGuide tools hard codes a website destination
for cross references and some html cross references assume
website root paths
*** IMPROVEMENTS
- bumped Doxygen from 1.4.x -> 1.6.3
- splits llvm/clang docs into 'main' and 'api' (doxygen) build trees
- provide consistent, reliable doc builds for both main+api docs
- support buid vs. install vs. website intentions
- support objdir builds
- document targets with 'make help'
- correct clean and uninstall operations
- use recursive dir delete only where absolutely necessary
- added call function fn.RMRF which safeguards against botched 'rm -rf';
if any target (or any variable is evaluated) which attempts
to remove any dirs which match a hard-coded 'safelist', a verbose
error will be printed and make will error-stop.
llvm-svn: 103213
of dependence and define trap values in terms of dependence, instead
of trying to cover the concept with a flurry of ad-hoc rules.
The dependence model isn't complete yet, but it's already much more
rigorous than the description it replaces.
llvm-svn: 102479
traps flowing through memory references, add some text to
better cover phi nodes and externally-visible side effects,
add an example of instructions being control-dependent
on a trap value, and reword some of the existing trap rules.
llvm-svn: 102399
the definition of the nsw and nuw flags to make use of it.
nsw was introduced to help optimizers answer yes to the following:
// Can we change i from i32 to i64 to eliminate the cast inside the loop?
for (int i = 0; i < n; ++i) A[i] *= 0.1;
// Can we assume that this loop will eventually terminate?
for (int i = 0; i <= n; ++i) A[i] *= 0.1;
In its current form, it isn't truly sufficient for either.
In the first case, if the increment overflows, it'll still have some
valid i32 value; sign-extending it will produce a value which is 33
homogeneous sign bits trailed by 31 independent undef bits. If i is
promoted to i64, it won't have those same values when it reaches that
point. (The compiler could recover here by reasoning about how i is
used by the load, but that's a lot more complicated and isn't always
possible.)
In the second case, there is no value for i which will be greater than
n, so having the increment return undef on overflow doesn't help.
Trap values are a formalization of some existing concepts that we have
about LLVM IR, and give the optimizers a better basis for answering yes
to both questions above.
llvm-svn: 102140
non-temporal. Fix from r96241 for botched encoding of MOVNTDQ.
Add documentation for !nontemporal metadata.
Add a simpler movnt testcase.
llvm-svn: 96386
This time it's for real! I am going to hook this up in the frontends as well.
The inliner has some experimental heuristics for dealing with the inline hint.
When given a -respect-inlinehint option, functions marked with the inline
keyword are given a threshold just above the default for -O3.
We need some experiments to determine if that is the right thing to do.
llvm-svn: 95466
datatypes on a given CPU. This is intended to allow instcombine and other
transformations to avoid converting big sequences of operations to an
inconvenient width, and will help clean up after SRoA. See also "Adding
legal integer sizes to TargetData" on Feb 1, 2009 on llvmdev, and PR3451.
Comments welcome.
llvm-svn: 86370
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
Dan Gohman