[ARM][MVE] MVE-I should not be disabled by -mfpu=none

Architecturally, it's allowed to have MVE-I without an FPU, thus
-mfpu=none should not disable MVE-I, or moves to/from FP-registers.

This patch removes `+/-fpregs` from features unconditionally added to
target feature list, depending on FPU and moves the logic to Clang
driver, where the negative form (`-fpregs`) is conditionally added to
the target features list for the cases of `-mfloat-abi=soft`, or
`-mfpu=none` without either `+mve` or `+mve.fp`. Only the negative
form is added by the driver, the positive one is derived from other
features in the backend.

Differential Revision: https://reviews.llvm.org/D71843

1 files changed, 0 insertions, 2 deletions

diff --git a/llvm/lib/Support/ARMTargetParser.cpp b/llvm/lib/Support/ARMTargetParser.cpp
index ce5daa7fe58..f2c22fd93c8 100644
--- a/llvm/lib/Support/ARMTargetParser.cpp
+++ b/llvm/lib/Support/ARMTargetParser.cpp
@@ -174,8 +174,6 @@ bool ARM::getFPUFeatures(unsigned FPUKind, std::vector<StringRef> &Features) {
     // under FPURestriction::None, which is the only FPURestriction in
     // which they would be valid (since FPURestriction::SP doesn't
     // exist).
-
-    {"+fpregs", "-fpregs", FPUVersion::VFPV2, FPURestriction::SP_D16},
     {"+vfp2", "-vfp2", FPUVersion::VFPV2, FPURestriction::D16},
     {"+vfp2sp", "-vfp2sp", FPUVersion::VFPV2, FPURestriction::SP_D16},
     {"+vfp3", "-vfp3", FPUVersion::VFPV3, FPURestriction::None},