[llvm] [LLVM][IR] Add native vector support to ConstantInt & ConstantFP. (PR #74502)

[Christian Ulmann via llvm-commits]

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@@ -35,6 +35,20 @@
 using namespace llvm;
 using namespace PatternMatch;
 
+// As set of temporary options to help migrate how splats are represented.
+static cl::opt<bool> UseConstantIntForFixedLengthSplat(
+    "use-constant-int-for-fixed-length-splat", cl::init(false), cl::Hidden,
+    cl::desc("Use ConstantInt's native fixed-length vector splat support."));
+static cl::opt<bool> UseConstantFPForFixedLengthSplat(
+    "use-constant-fp-for-fixed-length-splat", cl::init(false), cl::Hidden,
+    cl::desc("Use ConstantFP's native fixed-length vector splat support."));
+static cl::opt<bool> UseConstantIntForScalableSplat(
+    "use-constant-int-for-scalable-splat", cl::init(false), cl::Hidden,
+    cl::desc("Use ConstantInt's native scalable vector splat support."));
+static cl::opt<bool> UseConstantFPForScalableSplat(
+    "use-constant-fp-for-scalable-splat", cl::init(false), cl::Hidden,
+    cl::desc("Use ConstantFP's native scalable vector splat support."));
+
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Dinistro wrote:

@paulwalker-arm @nikic Do you think it makes sense to make these available in a header file? I tried to set them directly from within a custom tool, but failed to get access to these. For us, setting them via. the command line is impractical. 

https://github.com/llvm/llvm-project/pull/74502