This puts the functionality under control of a command-line option which is
off by default to avoid breaking existing setups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320197 91177308-0d34-0410-b5e6-96231b3b80d8
Generalize FixFunctionBitcasts to handle varargs functions. This in
particular fixes the case where clang bitcasts away a varargs when
calling a K&R-style function.
This avoids interacting with tricky ABI details because it operates
at the LLVM IR level before varargs ABI details are exposed.
This fixes PR35385.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319186 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The pass to fix function bitcasts generates thunks for functions that
are called directly with a mismatching signature. It was also generating
thunks in cases where the function was address-taken, causing aliasing
problems in otherwise valid cases.
This patch tightens the restrictions for when the pass runs.
Reviewers: sunfish, dschuff
Subscribers: jfb, sbc100, llvm-commits, aheejin
Differential Revision: https://reviews.llvm.org/D38640
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315326 91177308-0d34-0410-b5e6-96231b3b80d8
To facilitate this, add a new hidden command-line option to disable
the explicit-locals pass. That causes llc to emit invalid code that doesn't
have all locals converted to get_local/set_local, however it simplifies
testwriting in many cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296540 91177308-0d34-0410-b5e6-96231b3b80d8
WebAssembly varargs functions use a significantly different ABI than
non-varargs functions, and the current code in
WebAssemblyFixFunctionBitcasts doesn't handle that difference. For now,
just avoid creating wrapper functions in the presence of varargs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292645 91177308-0d34-0410-b5e6-96231b3b80d8
When we collect 2 uses of a function in FindUses and then RAUW when we
visit the first, we end up visiting the wrapper (because the second was
RAUW'd). We still want to use RAUW instead of just Use->set() because
it has special handling for Constants, so this patch just ensures that
only one use of each constant is added to the work list.
Differential Revision: https://reviews.llvm.org/D28504
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291603 91177308-0d34-0410-b5e6-96231b3b80d8
Gracefully leave code that performs function-pointer bitcasts implying
non-trivial pointer conversions alone, rather than aborting, since it's
just undefined behavior.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291326 91177308-0d34-0410-b5e6-96231b3b80d8
WebAssembly requires caller and callee signatures to match exactly. In LLVM,
there are a variety of circumstances where signatures may be mismatched in
practice, and one can bitcast a function address to another type to call it
as that type. This patch adds a pass which replaces bitcasted function
addresses with wrappers to replace the bitcasts.
This doesn't catch everything, but it does match many common cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291315 91177308-0d34-0410-b5e6-96231b3b80d8
