Summary:
Extend LDV so that stack slot offsets for spilled sub-registers
are added to the emitted debug locations. This is accomplished
by querying InstrInfo::getStackSlotRange().
With this change, LDV will add a DW_OP_plus_uconst operation to
the expression if a sub-register is spilled. Later on, PEI will
add an offset operation for the stack slot, meaning that we will
get expressions of the forms:
* {DW_OP_constu #fp-offset, DW_OP_minus,
DW_OP_plus_uconst #subreg-offset}
* {DW_OP_plus_const #fp-offset,
DW_OP_minus, DW_OP_plus_uconst #subreg-offset}
The two offset operations should ideally be merged.
Reviewers: rnk, aprantl, stoklund
Reviewed By: aprantl
Subscribers: dblaikie, bjope, nemanjai, JDevlieghere, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D51612
llvm-svn: 341659
565aeb86aa