[IPSCCP] Variable not visible at Og: (#77901)

https://bugs.llvm.org/show_bug.cgi?id=51559
https://github.com/llvm/llvm-project/issues/50901

IPSCCP pass removes the global variable and does not create a constant
expression for the initializer value.

Extend test coverage to include:
- half, bfloat types.
- checks for undef (int32 and ptr).

There is no support for:
- fp128, x86_fp80, ppc_fp128  types.
https://github.com/llvm/llvm-project/issues/88102

1 files changed, 5 insertions, 3 deletions

diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 380bac9..a42ef0c 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -3627,10 +3627,12 @@ DIExpression *llvm::getExpressionForConstant(DIBuilder &DIB, const Constant &C,
     return createIntegerExpression(C);
 
   auto *FP = dyn_cast<ConstantFP>(&C);
-  if (FP && (Ty.isFloatTy() || Ty.isDoubleTy())) {
+  if (FP && Ty.isFloatingPointTy() && Ty.getScalarSizeInBits() <= 64) {
     const APFloat &APF = FP->getValueAPF();
-    return DIB.createConstantValueExpression(
-        APF.bitcastToAPInt().getZExtValue());
+    APInt const &API = APF.bitcastToAPInt();
+    if (auto Temp = API.getZExtValue())
+      return DIB.createConstantValueExpression(static_cast<uint64_t>(Temp));
+    return DIB.createConstantValueExpression(*API.getRawData());
   }
 
   if (!Ty.isPointerTy())