[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:

Yes, `isInlinableLiteral16` can't because it can't tell `fp16` and `bf16` apart by just looking at the value. That's the reason I tried really hard to get rid of `isInlinableLiteral16` in #81345 and favors the explicit version.

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