[llvm] [GVN] Add code to disable scalar PRE (PR #190386)

[Antonio Frighetto via llvm-commits]

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@@ -291,7 +291,8 @@ NVPTXTargetMachine::getPredicatedAddrSpace(const Value *V) const {
 
 void NVPTXPassConfig::addEarlyCSEOrGVNPass() {
   if (getOptLevel() == CodeGenOptLevel::Aggressive)
-    addPass(createGVNPass());
+    // Disable scalar PRE due to Register Pressure increase
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antoniofrighetto wrote:

If possible, might be nice to add a test showing the register pressure increased (I think the one below is testing the option, right?), though not strong on this.

https://github.com/llvm/llvm-project/pull/190386