[NFC] Rename minnan and maxnan to minimum and maximum

Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.

Reviewers: arsenm, aheejin, dschuff, javed.absar

Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D53112

llvm-svn: 345218
diff --git a/llvm/unittests/Analysis/ValueTrackingTest.cpp b/llvm/unittests/Analysis/ValueTrackingTest.cpp
index f391ca1..d636517 100644
--- a/llvm/unittests/Analysis/ValueTrackingTest.cpp
+++ b/llvm/unittests/Analysis/ValueTrackingTest.cpp
@@ -149,7 +149,7 @@
   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
 }
 
-TEST_F(MatchSelectPatternTest, VectorFMinNaN) {
+TEST_F(MatchSelectPatternTest, VectorFMinimum) {
   parseAssembly(
       "define <4 x float> @test(<4 x float> %a) {\n"
       "  %1 = fcmp ule <4 x float> %a, \n"
@@ -177,7 +177,7 @@
   expectPattern({SPF_FMINNUM, SPNB_RETURNS_OTHER, true});
 }
 
-TEST_F(MatchSelectPatternTest, VectorNotFMinNaN) {
+TEST_F(MatchSelectPatternTest, VectorNotFMinimum) {
   parseAssembly(
       "define <4 x float> @test(<4 x float> %a) {\n"
       "  %1 = fcmp ule <4 x float> %a, \n"