[llvm] 92fe6c6 - Silence illegal address computation warning (#83244)

[via llvm-commits]

Author: Martin Wehking
Date: 2024-03-01T21:41:12+05:30
New Revision: 92fe6c61f900d6479f7ab708784c9e62d7523768

URL: https://github.com/llvm/llvm-project/commit/92fe6c61f900d6479f7ab708784c9e62d7523768
DIFF: https://github.com/llvm/llvm-project/commit/92fe6c61f900d6479f7ab708784c9e62d7523768.diff

LOG: Silence illegal address computation warning (#83244)

Add an assertion before an access of ValMappings to ensure that it is
within the array bounds.
Silence a static analyzer warning through this.

Added: 
    

Modified: 
    llvm/lib/Target/AMDGPU/AMDGPUGenRegisterBankInfo.def

Removed: 
    


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diff  --git a/llvm/lib/Target/AMDGPU/AMDGPUGenRegisterBankInfo.def b/llvm/lib/Target/AMDGPU/AMDGPUGenRegisterBankInfo.def
index d6a94c972340ea..0d41d5d2186fd8 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUGenRegisterBankInfo.def
+++ b/llvm/lib/Target/AMDGPU/AMDGPUGenRegisterBankInfo.def
@@ -284,6 +284,7 @@ const RegisterBankInfo::ValueMapping *getValueMapping(unsigned BankID,
     break;
   }
 
+  assert(Idx < std::size(ValMappings));
   assert(Log2_32_Ceil(Size) == Log2_32_Ceil(ValMappings[Idx].BreakDown->Length));
   assert(BankID == ValMappings[Idx].BreakDown->RegBank->getID());