[llvm-branch-commits] [llvm] Bundle operands to specify denormal modes (PR #136501)

[Matt Arsenault via llvm-branch-commits]

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@@ -678,6 +682,71 @@ fp::ExceptionBehavior CallBase::getExceptionBehavior() const {
   return fp::ebIgnore;
 }
 
+DenormalMode::DenormalModeKind CallBase::getInputDenormMode() const {
+  if (auto InDenormBundle = getOperandBundle(LLVMContext::OB_fp_control)) {
+    auto DenormOperand =
+        getBundleOperandByPrefix(*InDenormBundle, "denorm.in=");
+    if (DenormOperand) {
+      if (auto Mode = parseDenormalKindFromOperandBundle(*DenormOperand))
+        return *Mode;
+    } else {
+      return DenormalMode::IEEE;
+    }
+  }
+
+  if (!getParent())
+    return DenormalMode::IEEE;
+  const Function *F = getFunction();
+  if (!F)
+    return DenormalMode::IEEE;
+
+  Type *Ty = nullptr;
+  for (auto &A : args())
+    if (auto *T = A.get()->getType(); T->isFPOrFPVectorTy()) {
+      Ty = T;
+      break;
+    }
+  assert(Ty && "Some input argument must be of floating-point type");
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arsenm wrote:

This probably can't be an assert 

What happens if there are multiple input floating point type arguments, and each one has a differently controllable denormal mode?

For example, AMDGPU has some instructions with mixed half and float inputs, but those read from different FP mode controls (I haven't actually checked the right input mode bits are respected in these cases).

I'd probably just stop trying to report the mode if there are multiple input types 




https://github.com/llvm/llvm-project/pull/136501