The function to generate S_MOV_B64_IMM_PSEUDO was recently modified to
optimize AGPR to AGPR copy but it missed checking for the SGPR
clobbering for the S_MOV_B64_IMM_PSEUDO generation.
Differential Revision: https://reviews.llvm.org/D113005
On targets that do not support AGPR to AGPR copying directly, try to find the
defining accvgpr_write and propagate its source vgpr register to the copies
before register allocation so the source vgpr register does not get clobbered.
The postrapseudos pass also attempt to propagate the defining accvgpr_write but
if the register to propagate is clobbered, it will give up and create new
temporary vgpr registers instead.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D108830
This is to allow 64 bit constant rematerialization. If a constant
is split into two separate moves initializing sub0 and sub1 like
now RA cannot rematerizalize a 64 bit register.
This gives 10-20% uplift in a set of huge apps heavily using double
precession math.
Fixes: SWDEV-292645
Differential Revision: https://reviews.llvm.org/D104874
