diff options
| author | Eli Friedman <efriedma@quicinc.com> | 2020-05-16 17:55:18 -0700 |
|---|---|---|
| committer | Eli Friedman <efriedma@quicinc.com> | 2020-05-20 16:37:20 -0700 |
| commit | f26bdb539e8acef23e2a0370408521a6458001ee (patch) | |
| tree | 858d012071872321fd2f4417bd10e90b6c414a33 /llvm/lib/IR/ConstantFold.cpp | |
| parent | 770ba4f0516e9af7279767ae90e283c3755c0c97 (diff) | |
| download | llvm-f26bdb539e8acef23e2a0370408521a6458001ee.zip llvm-f26bdb539e8acef23e2a0370408521a6458001ee.tar.gz llvm-f26bdb539e8acef23e2a0370408521a6458001ee.tar.bz2 | |
Make Value::getPointerAlignment() return an Align, not a MaybeAlign.
If we don't know anything about the alignment of a pointer, Align(1) is
still correct: all pointers are at least 1-byte aligned.
Included in this patch is a bugfix for an issue discovered during this
cleanup: pointers with "dereferenceable" attributes/metadata were
assumed to be aligned according to the type of the pointer. This
wasn't intentional, as far as I can tell, so Loads.cpp was fixed to
stop making this assumption. Frontends may need to be updated. I
updated clang's handling of C++ references, and added a release note for
this.
Differential Revision: https://reviews.llvm.org/D80072
Diffstat (limited to 'llvm/lib/IR/ConstantFold.cpp')
| -rw-r--r-- | llvm/lib/IR/ConstantFold.cpp | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/llvm/lib/IR/ConstantFold.cpp b/llvm/lib/IR/ConstantFold.cpp index 8539b91f..d090eaa 100644 --- a/llvm/lib/IR/ConstantFold.cpp +++ b/llvm/lib/IR/ConstantFold.cpp @@ -1210,7 +1210,8 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1, MaybeAlign GVAlign; if (Module *TheModule = GV->getParent()) { - GVAlign = GV->getPointerAlignment(TheModule->getDataLayout()); + const DataLayout &DL = TheModule->getDataLayout(); + GVAlign = GV->getPointerAlignment(DL); // If the function alignment is not specified then assume that it // is 4. @@ -1221,7 +1222,7 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1, // increased code size (see https://reviews.llvm.org/D55115) // FIXME: This code should be deleted once existing targets have // appropriate defaults - if (!GVAlign && isa<Function>(GV)) + if (isa<Function>(GV) && !DL.getFunctionPtrAlign()) GVAlign = Align(4); } else if (isa<Function>(GV)) { // Without a datalayout we have to assume the worst case: that the |