Similar to 806761a7629df268c8aed49657aeccffa6bca449
-mtriple= specifies the full target triple while -march= merely sets the
architecture part of the default target triple (e.g. Windows, macOS),
leaving a target triple which may not make sense.
Therefore, -march= is error-prone and not recommended for tests without a target
triple. The issue has been benign as we recognize sparc*-apple-darwin as ELF instead
of rejecting it outrightly.
This adds support for using the L and H argument modifiers for twinword
operands in inline asm code, such as in:
```
%1 = tail call i64 asm sideeffect "rd %pc, ${0:L} ; srlx ${0:L}, 32, ${0:H}", "={o4}"()
```
This is needed by the Linux kernel.
Summary: The fX version of floating-point registers only supports
single precision. We need to map the name to dX for doubles and qX
for long doubles if we want getRegForInlineAsmConstraint() to be
able to pick the correct register class.
Reviewers: jyknight, venkatra
Reviewed By: jyknight
Subscribers: eraman, fedor.sergeev, jrtc27, llvm-commits
Differential Revision: https://reviews.llvm.org/D47258
llvm-svn: 333512
