[InstCombine] simplify fneg+fadd folds; NFC

Two cleanups:
1. As noted in D45453, we had tests that don't need FMF that were misplaced in the 'fast-math.ll' test file.
2. This removes the final uses of dyn_castFNegVal, so that can be deleted. We use 'match' now.

llvm-svn: 330126

2 files changed, 27 insertions, 24 deletions

diff --git a/llvm/test/Transforms/InstCombine/fadd.ll b/llvm/test/Transforms/InstCombine/fadd.ll
new file mode 100644
index 00000000000..f7eac8e14b6
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/fadd.ll
@@ -0,0 +1,27 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+; -x + y => y - x
+
+define float @fneg_op0(float %x, float %y) {
+; CHECK-LABEL: @fneg_op0(
+; CHECK-NEXT:    [[ADD:%.*]] = fsub float [[Y:%.*]], [[X:%.*]]
+; CHECK-NEXT:    ret float [[ADD]]
+;
+  %neg = fsub float -0.0, %x
+  %add = fadd float %neg, %y
+  ret float %add
+}
+
+; x + -y => x - y
+
+define float @fneg_op1(float %x, float %y) {
+; CHECK-LABEL: @fneg_op1(
+; CHECK-NEXT:    [[ADD:%.*]] = fsub float [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    ret float [[ADD]]
+;
+  %neg = fsub float -0.0, %y
+  %add = fadd float %x, %neg
+  ret float %add
+}
+
diff --git a/llvm/test/Transforms/InstCombine/fast-math.ll b/llvm/test/Transforms/InstCombine/fast-math.ll
index 132432f1013..81310fdd92b 100644
--- a/llvm/test/Transforms/InstCombine/fast-math.ll
+++ b/llvm/test/Transforms/InstCombine/fast-math.ll
@@ -406,30 +406,6 @@ define float @fold13_reassoc(float %x) {
   ret float %sub
 }
 
-; -x + y => y - x
-; This is always safe.  No FMF required.
-define float @fold14(float %x, float %y) {
-; CHECK-LABEL: @fold14(
-; CHECK-NEXT:    [[ADD:%.*]] = fsub float [[Y:%.*]], [[X:%.*]]
-; CHECK-NEXT:    ret float [[ADD]]
-;
-  %neg = fsub float -0.0, %x
-  %add = fadd float %neg, %y
-  ret float %add
-}
-
-; x + -y => x - y
-; This is always safe.  No FMF required.
-define float @fold15(float %x, float %y) {
-; CHECK-LABEL: @fold15(
-; CHECK-NEXT:    [[ADD:%.*]] = fsub float [[X:%.*]], [[Y:%.*]]
-; CHECK-NEXT:    ret float [[ADD]]
-;
-  %neg = fsub float -0.0, %y
-  %add = fadd float %x, %neg
-  ret float %add
-}
-
 ; (select X+Y, X-Y) => X + (select Y, -Y)
 ; This is always safe.  No FMF required.
 define float @fold16(float %x, float %y) {