[X86][SSE] Merge rL343373 into 7.0.1 - Fixed issue with v2i64 variable shifts on 32-bit targets

[RKSimon]

Bugzilla Link	39151
Resolution	FIXED
Resolved on	Oct 19, 2018 12:57
Version	trunk
OS	Windows NT
Blocks	#38454
CC	@topperc,@zmodem,@tstellar
Fixed by commit(s)	r343373 r344810

Extended Description

[X86][SSE] Fixed issue with v2i64 variable shifts on 32-bit targets

The shift amount might have peeked through a extract_subvector, altering the number of vector elements in the 'Amt' variable - so we were incorrectly calculating the ratio when peeking through bitcasts, resulting in incorrectly detecting splats.

[RKSimon]

assigned to @topperc

[tstellar]

Hi Craig,

Is this OK to merge?

https://reviews.llvm.org/rL343373

[topperc]

Yes, this is ok to merge.

[tstellar]

Merged: r344810