[llvm] ad87f24 - [InstSimplify] add more tests for fcmp+select; NFC

[Sanjay Patel via llvm-commits]

Author: Sanjay Patel
Date: 2019-11-04T08:23:08-05:00
New Revision: ad87f244b4228699806e757fedb39f8996c595f9

URL: https://github.com/llvm/llvm-project/commit/ad87f244b4228699806e757fedb39f8996c595f9
DIFF: https://github.com/llvm/llvm-project/commit/ad87f244b4228699806e757fedb39f8996c595f9.diff

LOG: [InstSimplify] add more tests for fcmp+select; NFC

The easy code fix won't catch non-canonical mismatched
constant patterns, so adding extra coverage for those in
case we decide that's important (but seems unlikely).

Added: 
    

Modified: 
    llvm/test/Transforms/InstSimplify/fcmp-select.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/InstSimplify/fcmp-select.ll b/llvm/test/Transforms/InstSimplify/fcmp-select.ll
index cea28639898a..8e04a9b46744 100644
--- a/llvm/test/Transforms/InstSimplify/fcmp-select.ll
+++ b/llvm/test/Transforms/InstSimplify/fcmp-select.ll
@@ -126,29 +126,29 @@ define float @oeq_zero_swapped_nsz(float %x) {
   ret float %cond
 }
 
-; X != 0.0 ? X : -0.0 --> X
+; X != 0.0 ? X : 0.0 --> X
 
 define double @une_zero_nsz(double %x) {
 ; CHECK-LABEL: @une_zero_nsz(
 ; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[X:%.*]], 0.000000e+00
-; CHECK-NEXT:    [[COND:%.*]] = select ninf nsz i1 [[CMP]], double [[X]], double -0.000000e+00
+; CHECK-NEXT:    [[COND:%.*]] = select ninf nsz i1 [[CMP]], double [[X]], double 0.000000e+00
 ; CHECK-NEXT:    ret double [[COND]]
 ;
   %cmp = fcmp une double %x, 0.0
-  %cond = select nsz ninf i1 %cmp, double %x, double -0.0
+  %cond = select nsz ninf i1 %cmp, double %x, double 0.0
   ret double %cond
 }
 
-; X != 0.0 ? -0.0 : X --> 0.0
+; X != 0.0 ? 0.0 : X --> 0.0
 
 define <2 x double> @une_zero_swapped_nsz(<2 x double> %x) {
 ; CHECK-LABEL: @une_zero_swapped_nsz(
-; CHECK-NEXT:    [[CMP:%.*]] = fcmp une <2 x double> [[X:%.*]], <double -0.000000e+00, double 0.000000e+00>
-; CHECK-NEXT:    [[COND:%.*]] = select nsz <2 x i1> [[CMP]], <2 x double> <double 0.000000e+00, double -0.000000e+00>, <2 x double> [[X]]
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une <2 x double> [[X:%.*]], zeroinitializer
+; CHECK-NEXT:    [[COND:%.*]] = select nsz <2 x i1> [[CMP]], <2 x double> zeroinitializer, <2 x double> [[X]]
 ; CHECK-NEXT:    ret <2 x double> [[COND]]
 ;
-  %cmp = fcmp une <2 x double> %x, <double -0.0, double 0.0>
-  %cond = select nsz <2 x i1> %cmp, <2 x double> <double 0.0, double -0.0>, <2 x double> %x
+  %cmp = fcmp une <2 x double> %x, <double 0.0, double 0.0>
+  %cond = select nsz <2 x i1> %cmp, <2 x double> <double 0.0, double 0.0>, <2 x double> %x
   ret <2 x double> %cond
 }
 
@@ -204,6 +204,34 @@ define <2 x double> @une_swapped_nsz(<2 x double> %x, <2 x double> %y) {
   ret <2 x double> %cond
 }
 
+; Harder - mismatched zero constants (not typical due to canonicalization):
+; X != 0.0 ? X : -0.0 --> X
+
+define double @une_zero_mismatch_nsz(double %x) {
+; CHECK-LABEL: @une_zero_mismatch_nsz(
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[X:%.*]], 0.000000e+00
+; CHECK-NEXT:    [[COND:%.*]] = select ninf nsz i1 [[CMP]], double [[X]], double -0.000000e+00
+; CHECK-NEXT:    ret double [[COND]]
+;
+  %cmp = fcmp une double %x, 0.0
+  %cond = select nsz ninf i1 %cmp, double %x, double -0.0
+  ret double %cond
+}
+
+; Even harder - mismatched vector zero constants (not typical due to canonicalization):
+; X != 0.0 ? -0.0 : X --> 0.0
+
+define <2 x double> @une_zero_mismatch_swapped_nsz(<2 x double> %x) {
+; CHECK-LABEL: @une_zero_mismatch_swapped_nsz(
+; CHECK-NEXT:    [[CMP:%.*]] = fcmp une <2 x double> [[X:%.*]], <double -0.000000e+00, double 0.000000e+00>
+; CHECK-NEXT:    [[COND:%.*]] = select nsz <2 x i1> [[CMP]], <2 x double> <double 0.000000e+00, double -0.000000e+00>, <2 x double> [[X]]
+; CHECK-NEXT:    ret <2 x double> [[COND]]
+;
+  %cmp = fcmp une <2 x double> %x, <double -0.0, double 0.0>
+  %cond = select nsz <2 x i1> %cmp, <2 x double> <double 0.0, double -0.0>, <2 x double> %x
+  ret <2 x double> %cond
+}
+
 define double @une_could_be_negzero(double %x, double %y) {
 ; CHECK-LABEL: @une_could_be_negzero(
 ; CHECK-NEXT:    [[CMP:%.*]] = fcmp une double [[X:%.*]], [[Y:%.*]]