[RISCV] Add support for lowering floating point inlineasm clobbers
This adds the required extension to RISC-V's getRegForInlineAsmConstraint
in order to be able to correctly distringuish between the 32 and 64-bit
floating point registers when the generic fX name appears in inlineasm
clobber contraints. It also adds a check to validate that callee saved
floating point registers are only saved in this case when a hard-float
ABI is selected.
Differential Revision: https://reviews.llvm.org/D64751
llvm-svn: 367397
diff --git a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
index ce7b859..78bc93d 100644
--- a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
+++ b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
@@ -2412,6 +2412,52 @@
}
}
+ // Since TargetLowering::getRegForInlineAsmConstraint uses the name of the
+ // TableGen record rather than the AsmName to choose registers for InlineAsm
+ // constraints, plus we want to match those names to the widest floating point
+ // register type available, manually select floating point registers here.
+ if (Subtarget.hasStdExtF() || Subtarget.hasStdExtD()) {
+ std::pair<unsigned, unsigned> FReg =
+ StringSwitch<std::pair<unsigned, unsigned>>(Constraint.lower())
+ .Case("{f0}", {RISCV::F0_32, RISCV::F0_64})
+ .Case("{f1}", {RISCV::F1_32, RISCV::F1_64})
+ .Case("{f2}", {RISCV::F2_32, RISCV::F2_64})
+ .Case("{f3}", {RISCV::F3_32, RISCV::F3_64})
+ .Case("{f4}", {RISCV::F4_32, RISCV::F4_64})
+ .Case("{f5}", {RISCV::F5_32, RISCV::F5_64})
+ .Case("{f6}", {RISCV::F6_32, RISCV::F6_64})
+ .Case("{f7}", {RISCV::F7_32, RISCV::F7_64})
+ .Case("{f8}", {RISCV::F8_32, RISCV::F8_64})
+ .Case("{f9}", {RISCV::F9_32, RISCV::F9_64})
+ .Case("{f10}", {RISCV::F10_32, RISCV::F10_64})
+ .Case("{f11}", {RISCV::F11_32, RISCV::F11_64})
+ .Case("{f12}", {RISCV::F12_32, RISCV::F12_64})
+ .Case("{f13}", {RISCV::F13_32, RISCV::F13_64})
+ .Case("{f14}", {RISCV::F14_32, RISCV::F14_64})
+ .Case("{f15}", {RISCV::F15_32, RISCV::F15_64})
+ .Case("{f16}", {RISCV::F16_32, RISCV::F16_64})
+ .Case("{f17}", {RISCV::F17_32, RISCV::F17_64})
+ .Case("{f18}", {RISCV::F18_32, RISCV::F18_64})
+ .Case("{f19}", {RISCV::F19_32, RISCV::F19_64})
+ .Case("{f20}", {RISCV::F20_32, RISCV::F20_64})
+ .Case("{f21}", {RISCV::F21_32, RISCV::F21_64})
+ .Case("{f22}", {RISCV::F22_32, RISCV::F22_64})
+ .Case("{f23}", {RISCV::F23_32, RISCV::F23_64})
+ .Case("{f24}", {RISCV::F24_32, RISCV::F24_64})
+ .Case("{f25}", {RISCV::F25_32, RISCV::F25_64})
+ .Case("{f26}", {RISCV::F26_32, RISCV::F26_64})
+ .Case("{f27}", {RISCV::F27_32, RISCV::F27_64})
+ .Case("{f28}", {RISCV::F28_32, RISCV::F28_64})
+ .Case("{f29}", {RISCV::F29_32, RISCV::F29_64})
+ .Case("{f30}", {RISCV::F30_32, RISCV::F30_64})
+ .Case("{f31}", {RISCV::F31_32, RISCV::F31_64})
+ .Default({-1U, -1U});
+ if (FReg.first != -1U)
+ return Subtarget.hasStdExtD()
+ ? std::make_pair(FReg.second, &RISCV::FPR64RegClass)
+ : std::make_pair(FReg.first, &RISCV::FPR32RegClass);
+ }
+
return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
}