[AMDGPU] Should return a value instead of llvm_unreachable in getLdsDwGranularity

changpeng · changpeng · commit 9befbe2e58d6 · 2025-11-17T13:25:21.000-08:00
We may compile  with no target, and do not expect a unreachanle failure.
diff --git a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
@@ -3554,7 +3554,7 @@ unsigned getLdsDwGranularity(const MCSubtargetInfo &ST) {
     return 320;
   if (ST.getFeatureBits().test(FeatureAddressableLocalMemorySize327680))
     return 512;
-  llvm_unreachable("Unknown Subtarget");
+  return 64; //In sync with getAddressableLocalMemorySize
 }
 
 bool isPackedFP32Inst(unsigned Opc) {

Original file line number	Diff line number	Diff line change
`@@ -3554,7 +3554,7 @@ unsigned getLdsDwGranularity(const MCSubtargetInfo &ST) {`
`3554`	`3554`	`return 320;`
`3555`	`3555`	`if (ST.getFeatureBits().test(FeatureAddressableLocalMemorySize327680))`
`3556`	`3556`	`return 512;`
`3557`		`- llvm_unreachable("Unknown Subtarget");`
	`3557`	`+ return 64; //In sync with getAddressableLocalMemorySize`
`3558`	`3558`	`}`
`3559`	`3559`
`3560`	`3560`	`bool isPackedFP32Inst(unsigned Opc) {`