Added verification for tied register for UNUSED_PRESERVE

Fix for VOP2b instructions was submitted in D40088.
Added SDWA dissassembler tests for VI.

Ping.
Matt, what do you think about latest changes in reivew?

Fixed latests issues from arsenm

Ping

Removed SIMergeSDWAPreserve pass.
Use tied registers to achieve same results

Resolved some issues

LGTM with small issue.

LGTM

LGTM

LGTM

LGTM

In D35350#808138, @arsenm wrote:

There should be an assembler test for omod being rejected with these. Doesn't the same also apply for clamp?

Added assembler tests

Re-used Opc

Fix comments from Matt

This change should in fact fix problem, but it is only workaround.
Ultimately problem is that instruction V_CVT_U32_F32 allow omod operand (see SIInstrInfo.td:1435). In fact this operand shouldn't be allowed here.
This should work as quickfix for assert if you need this. But I think it is better to provide full fix.

Hi,
I have no access to bug report: https://bugs.freedesktop.org/show_bug.cgi?id=101561
Can you send me failing .ll?

Removed changes from merge pseudo instrutions

I agree, it's better to remove assert ,rather them commenting them out.
Otherwise, LGTM

Ping

Removed generation check from constant bus verification.

Fixed issues in SIInstrInfo.cpp

This is good change. I wanted to propose it myself:)

LGTM
I think it's better if you submit this change. I will close my review (https://reviews.llvm.org/D33556).

Fixed linux macros

In D33132#761264, @artem.tamazov wrote:

In D33132#759329, @SamWot wrote:

Removed omod operand from pseudo instructions with integer dst

It seems that have been done for Gfx9 only. Any reason for this? Perhaps it is worth to add a comment.

Removed omod operand from pseudo instructions with integer dst

Rebased on top of master.
Renamed VI9 tests to GFX89.
Added commentary for SDWA on GFX9.

Simplified process. Got rid of PulledOut vector.

Small fix

Got rid of shared_ptr

Resolved some issues

Fixed and resubmitted in r299654

Submitted in r299202

Changed isImm() to foldToImm() that return Optional<int64_t>

Changes for latest comments

Add check for single use of src sdwa operand.

Cleanup for remaining comments.

In D30038#699461, @rampitec wrote:

I would like to see this patch fixed, submitted, and optimization enabled first, before new patterns are introduced.

I alredy either fixed or answered on comments to previous version. Currently I'm waiting for new comments or acceptance thats why I started working on new functionality.

Introduced new sdwa patterns

Fixed isSameBB

Added support for subregs.
Fixed most of previous comments.

Fixed issues

Ping