[llvm] [AMDGPU] Rewrite `getVregSrcForVT` with `!cond` (PR #81954)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-amdgpu

Author: Shilei Tian (shiltian)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/81954.diff


1 Files Affected:

- (modified) llvm/lib/Target/AMDGPU/SIInstrInfo.td (+8-9) 


``````````diff
diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.td b/llvm/lib/Target/AMDGPU/SIInstrInfo.td
index 4b7555de712c80..c0c1caeca59840 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.td
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.td
@@ -1528,15 +1528,14 @@ class getSOPSrcForVT<ValueType VT> {
 // Returns the vreg register class to use for source operand given VT
 class getVregSrcForVT<ValueType VT, bit IsTrue16 = 0, bit IsFake16 = 0> {
   RegisterOperand ret =
-      !if (!eq(VT.Size, 128), RegisterOperand<VReg_128>,
-           !if (!eq(VT.Size, 96), RegisterOperand<VReg_96>,
-                !if (!eq(VT.Size, 64), RegisterOperand<VReg_64>,
-                     !if (!eq(VT.Size, 48), RegisterOperand<VReg_64>,
-                          !if (!eq(VT.Size, 16),
-                               !if (IsTrue16,
-                                    !if (IsFake16, VGPRSrc_32_Lo128, VGPRSrc_16_Lo128),
-                                    RegisterOperand<VGPR_32>),
-                               RegisterOperand<VGPR_32>)))));
+  !cond(!eq(VT.Size, 128) : RegisterOperand<VReg_128>,
+        !eq(VT.Size, 96)  : RegisterOperand<VReg_96>,
+        !eq(VT.Size, 64)  : RegisterOperand<VReg_64>,
+        !eq(VT.Size, 48)  : RegisterOperand<VReg_64>,
+        !eq(VT.Size, 16)  : !if(IsTrue16,
+                                !if(IsFake16, VGPRSrc_32_Lo128, VGPRSrc_16_Lo128),
+                                RegisterOperand<VGPR_32>),
+        1                 : RegisterOperand<VGPR_32>);
 }
 
 class getSDWASrcForVT <ValueType VT> {

``````````

</details>


https://github.com/llvm/llvm-project/pull/81954