Add command line options to force function/loop alignments.

[mcrosier]

Summary

In short, these options can be used to override the target specified preferred/minimum function/loop alignments for testing purposes.

Chad

[gberry]

lib/CodeGen/MachineBlockPlacement.cpp

1334

If you move the max up before the if, you don't need to change the !Align check.

[mcrosier]

Address Geoff's comment.

[mcrosier]

A more straight forward solution.

[gberry]

LGTM with one caveat: we should double-check that the MachineBlock emission handles the case where the padding instruction bytes could be executed (i.e. that it knows to emit nops instead of just zeros).

[mcrosier]

In D15648#315796, @gberry wrote:

LGTM with one caveat: we should double-check that the MachineBlock emission handles the case where the padding instruction bytes could be executed (i.e. that it knows to emit nops instead of just zeros).

I didn't run into any issues across Spec200X. LGTM, per Geoff.

[mcrosier]

Committed r256571.