[llvm] 71f25ac - [InstSimplify] add tests for fcmp with casted op; NFC

[Sanjay Patel via llvm-commits]

Author: Sanjay Patel
Date: 2020-09-27T08:36:57-04:00
New Revision: 71f25ac8ca5de44d759da49df5549f3a89c2e536

URL: https://github.com/llvm/llvm-project/commit/71f25ac8ca5de44d759da49df5549f3a89c2e536
DIFF: https://github.com/llvm/llvm-project/commit/71f25ac8ca5de44d759da49df5549f3a89c2e536.diff

LOG: [InstSimplify] add tests for fcmp with casted op; NFC

This shows missing analysis in ValueTracking's isKnownNeverInfinity().

Added: 
    

Modified: 
    llvm/test/Transforms/InstSimplify/floating-point-compare.ll

Removed: 
    


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diff  --git a/llvm/test/Transforms/InstSimplify/floating-point-compare.ll b/llvm/test/Transforms/InstSimplify/floating-point-compare.ll
index d0864e78570b..0a7c15a6bb51 100644
--- a/llvm/test/Transforms/InstSimplify/floating-point-compare.ll
+++ b/llvm/test/Transforms/InstSimplify/floating-point-compare.ll
@@ -1138,3 +1138,99 @@ define <2 x i1> @is_finite_commute(<2 x i8> %x) {
   %r = fcmp one <2 x float> <float 0x7FF0000000000000, float 0x7FF0000000000000>, %cast
   ret <2 x i1> %r
 }
+
+; largest unsigned i15 = 2^15 - 1 = 32767
+; largest half (max exponent = 15 -> 2^15 * (1 + 1023/1024) = 65504
+
+define i1 @isKnownNeverInfinity_uitofp(i15 %x) {
+; CHECK-LABEL: @isKnownNeverInfinity_uitofp(
+; CHECK-NEXT:    ret i1 true
+;
+  %f = uitofp i15 %x to half
+  %r = fcmp une half %f, 0xH7c00
+  ret i1 %r
+}
+
+; negative test
+
+define i1 @isNotKnownNeverInfinity_uitofp(i16 %x) {
+; CHECK-LABEL: @isNotKnownNeverInfinity_uitofp(
+; CHECK-NEXT:    [[F:%.*]] = uitofp i16 [[X:%.*]] to half
+; CHECK-NEXT:    [[R:%.*]] = fcmp une half [[F]], 0xH7C00
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %f = uitofp i16 %x to half
+  %r = fcmp une half %f, 0xH7c00
+  ret i1 %r
+}
+
+define i1 @isKnownNeverNegativeInfinity_uitofp(i15 %x) {
+; CHECK-LABEL: @isKnownNeverNegativeInfinity_uitofp(
+; CHECK-NEXT:    ret i1 false
+;
+  %f = uitofp i15 %x to half
+  %r = fcmp oeq half %f, 0xHfc00
+  ret i1 %r
+}
+
+; uitofp can't be negative, so this still works.
+
+define i1 @isNotKnownNeverNegativeInfinity_uitofp(i16 %x) {
+; CHECK-LABEL: @isNotKnownNeverNegativeInfinity_uitofp(
+; CHECK-NEXT:    ret i1 false
+;
+  %f = uitofp i16 %x to half
+  %r = fcmp oeq half %f, 0xHfc00
+  ret i1 %r
+}
+
+; largest signed i16 = 2^15 - 1 = 32767
+; largest half (max exponent = 15 -> 2^15 * (1 + 1023/1024) = 65504
+
+define i1 @isKnownNeverInfinity_sitofp(i16 %x) {
+; CHECK-LABEL: @isKnownNeverInfinity_sitofp(
+; CHECK-NEXT:    [[F:%.*]] = sitofp i16 [[X:%.*]] to half
+; CHECK-NEXT:    [[R:%.*]] = fcmp une half [[F]], 0xH7C00
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %f = sitofp i16 %x to half
+  %r = fcmp une half %f, 0xH7c00
+  ret i1 %r
+}
+
+; negative test
+
+define i1 @isNotKnownNeverInfinity_sitofp(i17 %x) {
+; CHECK-LABEL: @isNotKnownNeverInfinity_sitofp(
+; CHECK-NEXT:    [[F:%.*]] = sitofp i17 [[X:%.*]] to half
+; CHECK-NEXT:    [[R:%.*]] = fcmp une half [[F]], 0xH7C00
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %f = sitofp i17 %x to half
+  %r = fcmp une half %f, 0xH7c00
+  ret i1 %r
+}
+
+define i1 @isKnownNeverNegativeInfinity_sitofp(i16 %x) {
+; CHECK-LABEL: @isKnownNeverNegativeInfinity_sitofp(
+; CHECK-NEXT:    [[F:%.*]] = sitofp i16 [[X:%.*]] to half
+; CHECK-NEXT:    [[R:%.*]] = fcmp oeq half [[F]], 0xHFC00
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %f = sitofp i16 %x to half
+  %r = fcmp oeq half %f, 0xHfc00
+  ret i1 %r
+}
+
+; negative test
+
+define i1 @isNotKnownNeverNegativeInfinity_sitofp(i17 %x) {
+; CHECK-LABEL: @isNotKnownNeverNegativeInfinity_sitofp(
+; CHECK-NEXT:    [[F:%.*]] = sitofp i17 [[X:%.*]] to half
+; CHECK-NEXT:    [[R:%.*]] = fcmp oeq half [[F]], 0xHFC00
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %f = sitofp i17 %x to half
+  %r = fcmp oeq half %f, 0xHfc00
+  ret i1 %r
+}