Revert "[SPIRV] Allow multiple FuncParamAttr decoration on the same id. (#166782)"

This reverts commit 2681497.
(This is being reverted because this commit needs
ebcf025, which was previously
reverted.)

Author: premanandrao

llvm/lib/Target/SPIRV/SPIRVModuleAnalysis.cpp

@@ -251,18 +251,17 @@ static InstrSignature instrToSignature(const MachineInstr &MI,
 <<<<<<< HEAD
 =======
     // The only decorations that can be applied more than once to a given <id>
-    // or structure member are FuncParamAttr (38), UserSemantic (5635),
-    // CacheControlLoadINTEL (6442), and CacheControlStoreINTEL (6443). For all
-    // the rest of decorations, we will only add to the signature the Opcode,
-    // the id to which it applies, and the decoration id, disregarding any
-    // decoration flags. This will ensure that any subsequent decoration with
-    // the same id will be deemed as a duplicate. Then, at the call site, we
-    // will be able to handle duplicates in the best way.
+    // or structure member are UserSemantic(5635), CacheControlLoadINTEL (6442),
+    // and CacheControlStoreINTEL (6443). For all the rest of decorations, we
+    // will only add to the signature the Opcode, the id to which it applies,
+    // and the decoration id, disregarding any decoration flags. This will
+    // ensure that any subsequent decoration with the same id will be deemed as
+    // a duplicate. Then, at the call site, we will be able to handle duplicates
+    // in the best way.
     unsigned Opcode = MI.getOpcode();
     if ((Opcode == SPIRV::OpDecorate) && i >= 2) {
       unsigned DecorationID = MI.getOperand(1).getImm();
-      if (DecorationID != SPIRV::Decoration::FuncParamAttr &&
-          DecorationID != SPIRV::Decoration::UserSemantic &&
+      if (DecorationID != SPIRV::Decoration::UserSemantic &&
           DecorationID != SPIRV::Decoration::CacheControlLoadINTEL &&
           DecorationID != SPIRV::Decoration::CacheControlStoreINTEL)
         continue;

llvm/test/CodeGen/SPIRV/spirv_param_decorations_quals.ll

@@ -7,11 +7,9 @@ entry:
 
 ; CHECK-SPIRV: OpDecorate %[[#PId:]] Volatile
 ; CHECK-SPIRV: OpDecorate %[[#PId]] FuncParamAttr NoAlias
-; CHECK-SPIRV: OpDecorate %[[#PId]] FuncParamAttr NoWrite
 ; CHECK-SPIRV: %[[#PId]] = OpFunctionParameter %[[#]]
 
 !7 = !{!"volatile"}
 !8 = !{i32 38, i32 4} ; FuncParamAttr NoAlias
-!11 = !{i32 38, i32 6} ; FuncParamAttr NoWrite
-!9 = !{!8, !11}
+!9 = !{!8}
 !10 = !{!9}