[llvm] AMDGPU: Allow operand folding between loop body and its preheader (PR #137022)

[Matt Arsenault via llvm-commits]

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@@ -23,6 +23,16 @@
 #define DEBUG_TYPE "si-fold-operands"
 using namespace llvm;
 
+static cl::opt<bool> SIFoldOperandsPreheader(
+    "amdgpu-si-fold-operands-preheader",
+    cl::desc("Enables operand folding between loop body and its preheader "),
+    cl::init(true));
+
+static cl::opt<int> SIFoldOperandsPreheaderThreshold(
+    "amdgpu-si-fold-operands-preheader-threshold", cl::init(100),
+    cl::desc("Threshold for operand folding hazard check. "
+             "Defaults to 100 MIs, upper limit 10000."));
+
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arsenm wrote:

Don't see why this would have an arbitrary a clamp 

https://github.com/llvm/llvm-project/pull/137022