Index: lib/Target/PowerPC/PPCFastISel.cpp
===================================================================
--- lib/Target/PowerPC/PPCFastISel.cpp
+++ lib/Target/PowerPC/PPCFastISel.cpp
@@ -213,12 +213,22 @@
   switch (Pred) {
     // These are not representable with any single compare.
     case CmpInst::FCMP_FALSE:
+    // For GT, LT and EQ, bc uses a normal form condition - LT, GT, EQ.
+    // The result UN doesn't trigger these predicates, which should be.
+    //
+    // On the other hand, testing !LT, !GT and !EQ against UN happens to be
+    // correct, since test will succeed, which should be.
     case CmpInst::FCMP_UEQ:
     case CmpInst::FCMP_UGT:
-    case CmpInst::FCMP_UGE:
     case CmpInst::FCMP_ULT:
-    case CmpInst::FCMP_ULE:
-    case CmpInst::FCMP_UNE:
+    // For GE, LE and NE, bc uses a negative form condition - !LT, !GT, !EQ.
+    // The result UN also triggers these predicates, which is wrong.
+    //
+    // On the other hand, testing GT, LT and EQ against UN happens to be
+    // correct, since test will fail on UN.
+    case CmpInst::FCMP_OGE:
+    case CmpInst::FCMP_OLE:
+    case CmpInst::FCMP_ONE:
     case CmpInst::FCMP_TRUE:
     default:
       return Optional<PPC::Predicate>();
@@ -232,7 +242,7 @@
     case CmpInst::ICMP_SGT:
       return PPC::PRED_GT;
 
-    case CmpInst::FCMP_OGE:
+    case CmpInst::FCMP_UGE:
     case CmpInst::ICMP_UGE:
     case CmpInst::ICMP_SGE:
       return PPC::PRED_GE;
@@ -242,12 +252,12 @@
     case CmpInst::ICMP_SLT:
       return PPC::PRED_LT;
 
-    case CmpInst::FCMP_OLE:
+    case CmpInst::FCMP_ULE:
     case CmpInst::ICMP_ULE:
     case CmpInst::ICMP_SLE:
       return PPC::PRED_LE;
 
-    case CmpInst::FCMP_ONE:
+    case CmpInst::FCMP_UNE:
     case CmpInst::ICMP_NE:
       return PPC::PRED_NE;
 
Index: test/CodeGen/PowerPC/fast-isel-fcmp-nan.ll
===================================================================
--- /dev/null
+++ test/CodeGen/PowerPC/fast-isel-fcmp-nan.ll
@@ -0,0 +1,187 @@
+; RUN: llc -mtriple powerpc64le-unknown-linux-gnu -fast-isel -O0 < %s | FileCheck %s
+
+define i1 @TestULT(double %t0) {
+; CHECK-LABEL: TestULT:
+; CHECK: mcrf
+; CHECK: blr
+entry:
+  %t1 = fcmp ult double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestULE(double %t0) {
+; CHECK-LABEL: TestULE:
+; CHECK: fcmpu
+; CHECK-NEXT: ble
+; CHECK: blr
+entry:
+  %t1 = fcmp ule double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestUNE(double %t0) {
+; CHECK-LABEL: TestUNE:
+; CHECK: fcmpu
+; CHECK-NEXT: bne
+; CHECK: blr
+entry:
+  %t1 = fcmp une double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestUEQ(double %t0) {
+; CHECK-LABEL: TestUEQ:
+; CHECK: mcrf
+; CHECK: blr
+entry:
+  %t1 = fcmp ueq double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestUGT(double %t0) {
+; CHECK-LABEL: TestUGT:
+; CHECK: mcrf
+; CHECK: blr
+entry:
+  %t1 = fcmp ugt double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestUGE(double %t0) {
+; CHECK-LABEL: TestUGE:
+; CHECK: fcmpu
+; CHECK-NEXT: bge
+; CHECK: blr
+entry:
+  %t1 = fcmp uge double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestOLT(double %t0) {
+; CHECK-LABEL: TestOLT:
+; CHECK: fcmpu
+; CHECK-NEXT: blt
+; CHECK: blr
+entry:
+  %t1 = fcmp olt double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestOLE(double %t0) {
+; CHECK-LABEL: TestOLE:
+; CHECK: mcrf
+; CHECK: blr
+entry:
+  %t1 = fcmp ole double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestONE(double %t0) {
+; CHECK-LABEL: TestONE:
+; CHECK: mcrf
+; CHECK: blr
+entry:
+  %t1 = fcmp one double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestOEQ(double %t0) {
+; CHECK-LABEL: TestOEQ:
+; CHECK: fcmpu
+; CHECK-NEXT: beq
+; CHECK: blr
+entry:
+  %t1 = fcmp oeq double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestOGT(double %t0) {
+; CHECK-LABEL: TestOGT:
+; CHECK: fcmpu
+; CHECK-NEXT: bgt
+; CHECK: blr
+entry:
+  %t1 = fcmp ogt double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}
+
+define i1 @TestOGE(double %t0) {
+; CHECK-LABEL: TestOGE:
+; CHECK: mcrf
+; CHECK: blr
+entry:
+  %t1 = fcmp oge double %t0, 0.000000e+00
+  br i1 %t1, label %good, label %bad
+
+bad:
+  ret i1 false
+
+good:
+  ret i1 true
+}