[ARC] Add more load/store variants.
On ARC ISA, general format of load instruction is this:
LD<zz><.x><.aa><.di> a, [b,c]
And general format of store is this:
ST<zz><.aa><.di> c, [b,s9]
Where:
<zz> is data size field and can be one of
<empty> (bits 00) - Word (32-bit), default behavior
B (bits 01) - Byte
H (bits 10) - Half-word (16-bit)
<.x> is data extend mode:
<empty> (bit 0) - If size is not Word(32-bit), then data is zero extended
X (bit 1) - If size is not Word(32-bit), then data is sign extended
<.aa> is address write-back mode:
<empty> (bits 00) - no write-back
.AW (bits 01) - Preincrement, base register updated pre memory transaction
.AB (bits 10) - Postincrement, base register updated post memory transaction
<.di> is cache bypass mode:
<empty> (bit 0) - Cached memory access, default mode
.DI (bit 1) - Non-cached data memory access
This patch adds these load/store instruction variants to the ARC backend.
Patch By Denis Antrushin! <denis@synopsys.com>
Differential Revision: https://reviews.llvm.org/D58980
llvm-svn: 356200