[llvm] [TLI] replace-with-veclib works with FRem Instruction. (PR #76166)

[Maciej Gabka via llvm-commits]

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@@ -69,52 +69,57 @@ Function *getTLIFunction(Module *M, FunctionType *VectorFTy,
   return TLIFunc;
 }
 
-/// Replace the call to the vector intrinsic ( \p CalltoReplace ) with a call to
-/// the corresponding function from the vector library ( \p TLIVecFunc ).
-static void replaceWithTLIFunction(CallInst &CalltoReplace, VFInfo &Info,
+/// Replace the Instruction \p I, that may be a vector intrinsic CallInst or
+/// the frem instruction,  with a call to the corresponding function from the
+/// vector library ( \p TLIVecFunc ).
+static void replaceWithTLIFunction(Instruction &I, VFInfo &Info,
                                    Function *TLIVecFunc) {
-  IRBuilder<> IRBuilder(&CalltoReplace);
-  SmallVector<Value *> Args(CalltoReplace.args());
+  IRBuilder<> IRBuilder(&I);
+  auto *CI = dyn_cast<CallInst>(&I);
+  SmallVector<Value *> Args(CI ? CI->args() : I.operands());
   if (auto OptMaskpos = Info.getParamIndexForOptionalMask()) {
-    auto *MaskTy = VectorType::get(Type::getInt1Ty(CalltoReplace.getContext()),
-                                   Info.Shape.VF);
+    auto *MaskTy =
+        VectorType::get(Type::getInt1Ty(I.getContext()), Info.Shape.VF);
     Args.insert(Args.begin() + OptMaskpos.value(),
                 Constant::getAllOnesValue(MaskTy));
   }
 
-  // Preserve the operand bundles.
+  // Preserve the operand bundles for CallInsts.
   SmallVector<OperandBundleDef, 1> OpBundles;
-  CalltoReplace.getOperandBundlesAsDefs(OpBundles);
+  if (CI)
+    CI->getOperandBundlesAsDefs(OpBundles);
+
   CallInst *Replacement = IRBuilder.CreateCall(TLIVecFunc, Args, OpBundles);
-  CalltoReplace.replaceAllUsesWith(Replacement);
+  I.replaceAllUsesWith(Replacement);
   // Preserve fast math flags for FP math.
   if (isa<FPMathOperator>(Replacement))
-    Replacement->copyFastMathFlags(&CalltoReplace);
+    Replacement->copyFastMathFlags(&I);
 }
 
-/// Returns true when successfully replaced \p CallToReplace with a suitable
-/// function taking vector arguments, based on available mappings in the \p TLI.
-/// Currently only works when \p CallToReplace is a call to vectorized
-/// intrinsic.
+/// Returns true when successfully replaced \p I with a suitable function taking
+/// vector arguments, based on available mappings in the \p TLI. Currently only
+/// works when \p I is a call to vectorized intrinsic or the FRem Instruction.
----------------
mgabka wrote:

nit: I think we write LLVM instruction names all smallcase, so should be "frem" as in lang ref, the Opcodes may follow a different convention.

https://github.com/llvm/llvm-project/pull/76166