===-------------------------------------------------------------------------===
+Compile:
+
+void foo(int *P) {
+ if (P) *P = 0;
+}
+
+into:
+
+_foo:
+ cmpwi cr0,r3,0
+ beqlr cr0
+ li r0,0
+ stw r0,0(r3)
+ blr
+
+This is effectively a simple form of predication.
+
+===-------------------------------------------------------------------------===
+
Teach the .td file to pattern match PPC::BR_COND to appropriate bc variant, so
we don't have to always run the branch selector for small functions.