6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-01-25 00:33:15 +00:00
Code Issues Projects Releases Wiki Activity

Define a no-pointer-overflow flag for GetElementPtr instructions.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76218 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2009-07-17 19:01:15 +00:00
parent 31cc426d9a
commit b4cfd15d99
1 changed files with 17 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
include/llvm/Instructions.h
View File

@ -573,6 +573,23 @@ public:
/// a constant offset between them.
bool hasAllConstantIndices() const;
/// hasNoPointerOverflow - Return true if this GetElementPtr is known to
/// never have overflow in the pointer addition portions of its effective
/// computation. GetElementPtr computation involves several phases;
/// overflow can be considered to occur in index typecasting, array index
/// scaling, and the addition of the base pointer with offsets. This flag
/// only applies to the last of these. The operands are added to the base
/// pointer one at a time from left to right. This function returns false
/// if any of these additions results in an address value which is not
/// known to be within the allocated address space that the base pointer
/// points into, or within one element (of the original allocation) past
/// the end.
bool hasNoPointerOverflow() const {
return SubclassOptionalData & (1 << 0);
}
void setHasNoPointerOverflow(bool B) {
SubclassOptionalData = (SubclassOptionalData & ~(1 << 0)) | (B << 0);
}
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const GetElementPtrInst *) { return true; }