[MC] Suppress .Lcfi labels when emitting textual assembly
Audit RequiredrL315259

Description

[MC] Suppress .Lcfi labels when emitting textual assembly

Summary:
This suppresses the generation of .Lcfi labels in our textual assembler.
It was annoying that this generated cascading .Lcfi labels:

llc foo.ll -o - | llvm-mc | llvm-mc

After three trips through MCAsmStreamer, we'd have three labels in the
output when none are necessary. We should only bother creating the
labels and frame data when making a real object file.

This supercedes D38605, which moved the entire .seh_ implementation into
MCObjectStreamer.

This has the advantage that we do more checking when emitting textual
assembly, as a minor efficiency cost. Outputting textual assembly is not
performance critical, so this shouldn't matter.

Reviewers: majnemer, MatzeB

Subscribers: qcolombet, nemanjai, javed.absar, eraman, hiraditya, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D38638

Details

Auditors
grosbach
Committed
rnkOct 9 2017, 5:57 PM
Differential Revision
D38638: [MC] Suppress .Lcfi labels when emitting textual assembly
Parents
rL315258: Fix Wasm build after r315254
Branches
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Tags
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