Commit Graph

2 Commits

Author SHA1 Message Date
Adrian Prantl 1c8ed2081f Skip test with older versions of clang
llvm-svn: 343695
2018-10-03 16:24:14 +00:00
Adrian Prantl f796e763b2 DWARFExpression: Resolve file addresses in the linked module
This is a follow-up to https://reviews.llvm.org/D46362.

When evaluating a complex expression in DWARFExpression::Evaluate,
file addresses must be resolved to load addresses before we can
perform operations such as DW_OP_deref on them.

For this the address goes through three steps

1. Read the file address as stored in the DWARF
2. Link/relocate the file address (when reading from a .dSYM, this is a no-op)
3. Convert the file address to a load address.

D46362 implemented step (3) by resolving the file address using the
Module that the original DWARF came from. In the case of a dSYM that
is correct, but when reading from .o files, we need to look up
relocated/linked addresses, so the right place to look them up is the
current frame's module. This patch fixes that by setting the
expression's Module to point to the linked debugmap object.

A word a bout the unorthodox testcase: The motivating testcase for
this fix is in Swift, but I managed to hand-modify LLVM-IR for a
trivial C program to exhibit the same problem, so we can fix this in
llvm.org.

rdar://problem/44689915

Differential Revision: https://reviews.llvm.org/D52678

llvm-svn: 343612
2018-10-02 17:50:42 +00:00