If the arch is P8, we will select XFLOAD to load the floating point, and then, expand it to vsx and non-vsx X-form instruction post RA. This patch is trying to convert the X-form to D-form if it meets the requirement that one operand of the x-form inst is the special Zero register, and another operand fed by add inst. i.e.
y = add imm, reg
LFDX. 0, y
-->
LFD imm(reg)
Reviewers: Nemanjai
Differential Revision: https://reviews.llvm.org/D49007
llvm-svn: 340149
The match pattern in the definition of LXSDX is xoaddr, so the Pseudo
instruction XFLOADf64 never gets selected. XFLOADf64 expands to LXSDX/LFDX post
RA based on the register pressure. To avoid ambiguity, we need to remove the
select pattern for LXSDX, same as what was done for LXSD. STXSDX also have
the same issue.
Patch by Qing Shan Zhang (steven.zhang).
Differential Revision: https://reviews.llvm.org/D47178
llvm-svn: 333150
The VSX stores are sometimes generated with a undefined index register, causing %noreg to be used and R0 to be emitted later on. The semantics of the VSX store (e.g. stdsdx) requires R0 to be used as base if we want zero to be used in the computation of the effective address instead of the content of R0. This patch checks if no index register was generated and forces R0 to be used as base address.
llvm-svn: 232486
QingShan Zhang