[PATCH] D24279: [InstCombine] canonicalize vector select with constant vector condition to shuffle

[David Majnemer via llvm-commits]

majnemer added inline comments.

================
Comment at: lib/Transforms/InstCombine/InstCombineSelect.cpp:965
@@ +964,3 @@
+    unsigned NumElts = CondVal->getType()->getVectorNumElements();
+    SmallVector<Constant *, 16> Mask(NumElts);
+    Type *Int32Ty = Type::getInt32Ty(CondVal->getContext());
----------------
I'd just reserve `NumElts` and push_back in the loop.

================
Comment at: lib/Transforms/InstCombine/InstCombineSelect.cpp:966
@@ +965,3 @@
+    SmallVector<Constant *, 16> Mask(NumElts);
+    Type *Int32Ty = Type::getInt32Ty(CondVal->getContext());
+    for (unsigned int i = 0; i != NumElts; ++i) {
----------------
Might be shorter to use `Builder->getInt32Ty()`

================
Comment at: lib/Transforms/InstCombine/InstCombineSelect.cpp:967
@@ +966,3 @@
+    Type *Int32Ty = Type::getInt32Ty(CondVal->getContext());
+    for (unsigned int i = 0; i != NumElts; ++i) {
+      Constant *Elt = CondC->getAggregateElement(i);
----------------
I think we'd just use `unsigned`.

================
Comment at: lib/Transforms/InstCombine/InstCombineSelect.cpp:968
@@ +967,3 @@
+    for (unsigned int i = 0; i != NumElts; ++i) {
+      Constant *Elt = CondC->getAggregateElement(i);
+      if (Elt->isOneValue()) {
----------------
Can't this return null?


https://reviews.llvm.org/D24279