Module flags are key-value pairs associated with the module. They include a
'behavior' value, indicating how module flags react when mergine two
files. Normally, it's just the union of the two module flags. But if two module
flags have the same key, then the resulting flags are dictated by the behaviors.
Allowable behaviors are:
Error
Emits an error if two values disagree.
Warning
Emits a warning if two values disagree.
Require
Emits an error when the specified value is not present
or doesn't have the specified value. It is an error for
two (or more) llvm.module.flags with the same ID to have
the Require behavior but different values. There may be
multiple Require flags per ID.
Override
Uses the specified value if the two values disagree. It
is an error for two (or more) llvm.module.flags with the
same ID to have the Override behavior but different
values.
llvm-svn: 150300
but with a critical fix to the SelectionDAG code that optimizes copies
from strings into immediate stores: the previous code was stopping reading
string data at the first nul. Address this by adding a new argument to
llvm::getConstantStringInfo, preserving the behavior before the patch.
llvm-svn: 149800
The purpose of refactoring is to hide operand roles from SwitchInst user (programmer). If you want to play with operands directly, probably you will need lower level methods than SwitchInst ones (TerminatorInst or may be User). After this patch we can reorganize SwitchInst operands and successors as we want.
What was done:
1. Changed semantics of index inside the getCaseValue method:
getCaseValue(0) means "get first case", not a condition. Use getCondition() if you want to resolve the condition. I propose don't mix SwitchInst case indexing with low level indexing (TI successors indexing, User's operands indexing), since it may be dangerous.
2. By the same reason findCaseValue(ConstantInt*) returns actual number of case value. 0 means first case, not default. If there is no case with given value, ErrorIndex will returned.
3. Added getCaseSuccessor method. I propose to avoid usage of TerminatorInst::getSuccessor if you want to resolve case successor BB. Use getCaseSuccessor instead, since internal SwitchInst organization of operands/successors is hidden and may be changed in any moment.
4. Added resolveSuccessorIndex and resolveCaseIndex. The main purpose of these methods is to see how case successors are really mapped in TerminatorInst.
4.1 "resolveSuccessorIndex" was created if you need to level down from SwitchInst to TerminatorInst. It returns TerminatorInst's successor index for given case successor.
4.2 "resolveCaseIndex" converts low level successors index to case index that curresponds to the given successor.
Note: There are also related compatability fix patches for dragonegg, klee, llvm-gcc-4.0, llvm-gcc-4.2, safecode, clang.
llvm-svn: 149481
The pass pointer should never be referenced after sending it to
schedulePass(), which may delete the pass. To fix this bug I had to
clean up the design leading to more goodness.
You may notice now that any non-analysis pass is printed. So things like loop-simplify and lcssa show up, while target lib, target data, alias analysis do not show up. Normally, analysis don't mutate the IR, but you can now check this by using both -print-after and -print-before. The effects of analysis will now show up in between the two.
The llc path is still in bad shape. But I'll be improving it in my next checkin. Meanwhile, print-machineinstrs still works the same way. With print-before/after, many llc passes that were not printed before now are, some of these should be converted to analysis. A few very important passes, isel and scheduler, are not properly initialized, so not printed.
llvm-svn: 149480
kicking in the big win of ConstantDataArray. As part of this, change
the implementation of GetConstantStringInfo in ValueTracking to work
with ConstantDataArray (and not ConstantArray) making it dramatically,
amazingly, more efficient in the process and renaming it to
getConstantStringInfo.
This keeps around a GetConstantStringInfo entrypoint that (grossly)
forwards to getConstantStringInfo and constructs the std::string
required, but existing clients should move over to
getConstantStringInfo instead.
llvm-svn: 149351
ConstantExpr::getWithOperandReplaced and ConstantExpr::replaceUsesOfWithOnConstant
in terms of ConstantExpr::getWithOperands. While we're at it,
make sure that ConstantExpr::getWithOperands covers all instructions: it was
missing insert/extractvalue.
llvm-svn: 149076
ConstantVector. Fix some outright bugs in the implementation of
ConstantArray and Constant struct, which would cause us to not make
one big UndefValue when asking for an array/struct with all undef
elements. Enhance Constant::isAllOnesValue to work with
ConstantDataVector.
llvm-svn: 149021
to reduce the number of cast<>'s we have. This allows someone to use
things like Ty->getVectorNumElements() instead of
cast<VectorType>(Ty)->getNumElements() when you know that a type is a
vector.
It would be a great general cleanup to move the codebase to use these,
I will do so in the code I'm touching.
llvm-svn: 148999
add a ConstantDataArray::getString method that corresponds to the (to be
removed) StringRef version of ConstantArray::get, but is dramatically more
efficient.
llvm-svn: 148804
and clean up some other misc stuff. Unlike ConstantArray, we will
prefer to emit .fill directives for "String" arrays that all have
the same value, since they are denser than emitting a .ascii
llvm-svn: 148793
Andrew Trick