AMDGPU: Use source modifiers with f16->f32 conversions

The operand types were defined to fit the fp16_to_fp node, which
has the half as an integer type. v_cvt_f32_f16 does support
source modifiers, so change this to have an FP type and modifiers.

For targets without legal f16, this requires recognizing the
bit operations and trying to produce them.

llvm-svn: 293857

1 files changed, 8 insertions, 2 deletions

diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
index e718b459ec3..51006589b5c 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -1824,7 +1824,8 @@ bool SIInstrInfo::isInlineConstant(const APInt &Imm) const {
     return AMDGPU::isInlinableLiteral64(Imm.getSExtValue(),
                                         ST.hasInv2PiInlineImm());
   case 16:
-    return AMDGPU::isInlinableLiteral16(Imm.getSExtValue(),
+    return ST.has16BitInsts() &&
+           AMDGPU::isInlinableLiteral16(Imm.getSExtValue(),
                                         ST.hasInv2PiInlineImm());
   default:
     llvm_unreachable("invalid bitwidth");
@@ -1854,8 +1855,13 @@ bool SIInstrInfo::isInlineConstant(const MachineOperand &MO,
   }
   case 16: {
     if (isInt<16>(Imm) || isUInt<16>(Imm)) {
+      // A few special case instructions have 16-bit operands on subtargets
+      // where 16-bit instructions are not legal.
+      // TODO: Do the 32-bit immediates work? We shouldn't really need to handle
+      // constants in these cases
       int16_t Trunc = static_cast<int16_t>(Imm);
-      return AMDGPU::isInlinableLiteral16(Trunc, ST.hasInv2PiInlineImm());
+      return ST.has16BitInsts() &&
+             AMDGPU::isInlinableLiteral16(Trunc, ST.hasInv2PiInlineImm());
     }
 
     return false;