[llvm] e78c30a - [ValueTracking] Add logic for `isKnownNonZero(umin X, Y)`

[Noah Goldstein via llvm-commits]

Author: Noah Goldstein
Date: 2023-04-30T10:06:46-05:00
New Revision: e78c30a10fe73c03843604a9d06ac55b87fda735

URL: https://github.com/llvm/llvm-project/commit/e78c30a10fe73c03843604a9d06ac55b87fda735
DIFF: https://github.com/llvm/llvm-project/commit/e78c30a10fe73c03843604a9d06ac55b87fda735.diff

LOG: [ValueTracking] Add logic for `isKnownNonZero(umin X, Y)`

`(umin X, Y) != 0` -> `X != 0 && Y != 0`

Alive2 Link:
    https://alive2.llvm.org/ce/z/AQh67i

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D149416

Added: 
    

Modified: 
    llvm/lib/Analysis/ValueTracking.cpp
    llvm/test/Analysis/ValueTracking/known-non-zero.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 75f5e40e993c..8551de669475 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -2942,6 +2942,9 @@ bool isKnownNonZero(const Value *V, const APInt &DemandedElts, unsigned Depth,
             isKnownNonZero(II->getArgOperand(1), DemandedElts, Depth, Q))
           return true;
         break;
+      case Intrinsic::umin:
+        return isKnownNonZero(II->getArgOperand(0), DemandedElts, Depth, Q) &&
+               isKnownNonZero(II->getArgOperand(1), DemandedElts, Depth, Q);
       case Intrinsic::cttz:
         return computeKnownBits(II->getArgOperand(0), DemandedElts, Depth, Q)
             .Zero[0];

diff  --git a/llvm/test/Analysis/ValueTracking/known-non-zero.ll b/llvm/test/Analysis/ValueTracking/known-non-zero.ll
index a01a9cd59197..5f45d30d65fb 100644
--- a/llvm/test/Analysis/ValueTracking/known-non-zero.ll
+++ b/llvm/test/Analysis/ValueTracking/known-non-zero.ll
@@ -994,10 +994,7 @@ define i1 @umin_nonzero(i8 %xx, i8 %yy, i8 %ind) {
 ; CHECK-NEXT:    call void @llvm.assume(i1 [[X_NZ]])
 ; CHECK-NEXT:    [[Y_NZ:%.*]] = icmp ne i8 [[YY:%.*]], 0
 ; CHECK-NEXT:    call void @llvm.assume(i1 [[Y_NZ]])
-; CHECK-NEXT:    [[X:%.*]] = call i8 @llvm.umin.i8(i8 [[XX]], i8 [[YY]])
-; CHECK-NEXT:    [[Z:%.*]] = or i8 [[X]], [[IND:%.*]]
-; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[Z]], 0
-; CHECK-NEXT:    ret i1 [[R]]
+; CHECK-NEXT:    ret i1 false
 ;
   %x_nz = icmp ne i8 %xx, 0
   call void @llvm.assume(i1 %x_nz)
@@ -1032,10 +1029,7 @@ define i1 @smin_nonzero(i8 %xx, i8 %yy, i8 %ind) {
 ; CHECK-NEXT:    call void @llvm.assume(i1 [[X_NZ]])
 ; CHECK-NEXT:    [[Y_NZ:%.*]] = icmp ne i8 [[YY:%.*]], 0
 ; CHECK-NEXT:    call void @llvm.assume(i1 [[Y_NZ]])
-; CHECK-NEXT:    [[X:%.*]] = call i8 @llvm.umin.i8(i8 [[XX]], i8 [[YY]])
-; CHECK-NEXT:    [[Z:%.*]] = or i8 [[X]], [[IND:%.*]]
-; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[Z]], 0
-; CHECK-NEXT:    ret i1 [[R]]
+; CHECK-NEXT:    ret i1 false
 ;
   %x_nz = icmp ne i8 %xx, 0
   call void @llvm.assume(i1 %x_nz)