[DebugInfo] Correctly coalesce DBG_VALUEs that mix direct and indirect values
Summary:
This should fix a regression introduced by r313786, which switched from
MachineInstr::isIndirectDebugValue() to checking if operand 1 is an
immediate. I didn't have a test case for it until now.
A single UserValue, which approximates a user variable, may have many
DBG_VALUE instructions that disagree about whether the variable is in
memory or in a virtual register. This will become much more common once
we have llvm.dbg.addr, but you can construct such a test case manually
today with llvm.dbg.value.
Before this change, we would get two UserValues: one for direct and one
for indirect DBG_VALUE instructions describing the same variable. If we
build separate interval maps for direct and indirect locations, we will
end up accidentally coalescing identical DBG_VALUE intervals that need
to remain separate because they are broken up by intervals of the
opposite direct-ness.
Reviewers: aprantl
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D37932
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@314819 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed