[clang] [llvm] [RFC][AMDGPU] Use `bf16` instead of `i16` for bfloat (PR #80908)

[Shilei Tian via cfe-commits]

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@@ -4185,9 +4185,17 @@ bool SIInstrInfo::isInlineConstant(const MachineOperand &MO,
   case AMDGPU::OPERAND_REG_INLINE_C_V2FP16:
   case AMDGPU::OPERAND_REG_INLINE_AC_V2FP16:
     return AMDGPU::isInlinableLiteralV2F16(Imm);
+  case AMDGPU::OPERAND_REG_IMM_V2BF16:
+  case AMDGPU::OPERAND_REG_INLINE_C_V2BF16:
+  case AMDGPU::OPERAND_REG_INLINE_AC_V2BF16:
+    return AMDGPU::isInlinableLiteralV2BF16(Imm);
+  case AMDGPU::OPERAND_REG_IMM_BF16:
   case AMDGPU::OPERAND_REG_IMM_FP16:
+  case AMDGPU::OPERAND_REG_IMM_BF16_DEFERRED:
   case AMDGPU::OPERAND_REG_IMM_FP16_DEFERRED:
+  case AMDGPU::OPERAND_REG_INLINE_C_BF16:
   case AMDGPU::OPERAND_REG_INLINE_C_FP16:
+  case AMDGPU::OPERAND_REG_INLINE_AC_BF16:
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shiltian wrote:

Okay, I copied `isInlinableLiteralBF16` from https://github.com/llvm/llvm-project/pull/81345. Initially I thought https://github.com/llvm/llvm-project/pull/81345 would be landed before this one, but I went down that rabbit hole and still didn't make it fully work.

https://github.com/llvm/llvm-project/pull/80908