[flang-commits] [flang] [Flang] Force lowering to Complex for AMDGPU (PR #144927)

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llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-flang-fir-hlfir

Author: Akash Banerjee (TIFitis)

<details>
<summary>Changes</summary>

Avoid libm when targeting AMDGPU as those symbols are not available on the device and we rely on MLIR complex operations to later map to OCML calls.

PRs #<!-- -->144924 & #<!-- -->144926 add additional related support.

---
Full diff: https://github.com/llvm/llvm-project/pull/144927.diff


1 Files Affected:

- (modified) flang/lib/Optimizer/Builder/IntrinsicCall.cpp (+5-2) 


``````````diff
diff --git a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
index 178b6770d6b53..2ca7f2784aab3 100644
--- a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
+++ b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
@@ -1228,8 +1228,11 @@ mlir::Value genComplexMathOp(fir::FirOpBuilder &builder, mlir::Location loc,
   llvm::StringRef mathLibFuncName = mathOp.runtimeFunc;
   if (!mathLibFuncName.empty()) {
     // If we enabled MLIR complex or can use approximate operations, we should
-    // NOT use libm.
-    if (!forceMlirComplex && !canUseApprox) {
+    // NOT use libm. Avoid libm when targeting AMDGPU as those symbols are not
+    // available on the device and we rely on MLIR complex operations to
+    // later map to OCML calls.
+    bool isAMDGPU = fir::getTargetTriple(builder.getModule()).isAMDGCN();
+    if (!forceMlirComplex && !canUseApprox && !isAMDGPU) {
       result = genLibCall(builder, loc, mathOp, mathLibFuncType, args);
       LLVM_DEBUG(result.dump(); llvm::dbgs() << "\n");
       return result;

``````````

</details>


https://github.com/llvm/llvm-project/pull/144927