[flang-commits] [flang] [llvm] [flang][PPC] Implement ieee_set_status and ieee_get_status for AIX (PR #215618)

[Daniel Chen via flang-commits]

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@@ -5210,11 +5210,81 @@ template <bool isGet, bool isModes>
 void IntrinsicLibrary::genIeeeGetOrSetModesOrStatus(
     llvm::ArrayRef<fir::ExtendedValue> args) {
   assert(args.size() == 1);
+  if constexpr (!isModes) {
+    llvm::Triple triple = fir::getTargetTriple(builder.getModule());
+    mlir::Type i32Ty = builder.getIntegerType(32);
+    mlir::Type i32PtrTy = builder.getRefType(i32Ty);
+    if (triple.isOSAIX()) {
+      // On AIX, fegetenv/fesetenv does not round-trip the FPSCR trap-enable
+      // bits [7:3].
+      //
+      // ieee_status_type.__data layout:
+      //   bytes  [0, 20) - fenv_t saved by fegetenv / restored by fesetenv
+      //   bytes [20, 28) - raw FPSCR double from mffs (trap-enable bits [7:3])
+      static constexpr int kAIXFenvTSize = 20; // sizeof(fenv_t) on AIX
----------------
DanielCChen wrote:

Instead of hardcode the value, shall we inquire the runtime 
```
size_t RTNAME(GetFenvTSize)(void) { return sizeof(fenv_t); }
```


https://github.com/llvm/llvm-project/pull/215618