[llvm] ca0d3c9 - [ConstraintElim] Add bottom tested loops with EQ predicates.

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2023-08-17T11:09:19+01:00
New Revision: ca0d3c99e109e5ed81b244712f0fa2d24b8812b1

URL: https://github.com/llvm/llvm-project/commit/ca0d3c99e109e5ed81b244712f0fa2d24b8812b1
DIFF: https://github.com/llvm/llvm-project/commit/ca0d3c99e109e5ed81b244712f0fa2d24b8812b1.diff

LOG: [ConstraintElim] Add bottom tested loops with EQ predicates.

Extra test coverage for D152730.

Added: 
    

Modified: 
    llvm/test/Transforms/ConstraintElimination/loops-bottom-tested-base.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/ConstraintElimination/loops-bottom-tested-base.ll b/llvm/test/Transforms/ConstraintElimination/loops-bottom-tested-base.ll
index 0e2cbc4370e93e..3dbea9496da8d7 100644
--- a/llvm/test/Transforms/ConstraintElimination/loops-bottom-tested-base.ll
+++ b/llvm/test/Transforms/ConstraintElimination/loops-bottom-tested-base.ll
@@ -96,3 +96,90 @@ loop:
 exit:
   ret void
 }
+
+declare void @clobber()
+
+define void @eq_exit_check_constant_int() {
+; CHECK-LABEL: @eq_exit_check_constant_int(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[LOOP:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 1, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
+; CHECK-NEXT:    call void @clobber()
+; CHECK-NEXT:    [[C:%.*]] = icmp eq i64 [[IV]], 2
+; CHECK-NEXT:    br i1 [[C]], label [[EXIT:%.*]], label [[LOOP]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+entry:
+  br label %loop
+
+loop:
+  %iv = phi i64 [ 1, %entry], [ %iv.next, %loop ]
+  %iv.next = add nuw i64 %iv, 1
+  call void @clobber()
+  %c = icmp eq i64 %iv, 2
+  br i1 %c, label %exit, label %loop
+
+exit:
+  ret void
+}
+
+define void @eq_exit_check_variable(i64 %N) {
+; CHECK-LABEL: @eq_exit_check_variable(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[PRECOND:%.*]] = icmp eq i64 [[N:%.*]], 0
+; CHECK-NEXT:    br i1 [[PRECOND]], label [[EXIT:%.*]], label [[LOOP:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 1, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
+; CHECK-NEXT:    call void @clobber()
+; CHECK-NEXT:    [[EXITCOND86_NOT_I_I:%.*]] = icmp eq i64 [[IV]], [[N]]
+; CHECK-NEXT:    br i1 [[EXITCOND86_NOT_I_I]], label [[EXIT]], label [[LOOP]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+entry:
+  %precond = icmp eq i64 %N, 0
+  br i1 %precond, label %exit, label %loop
+
+loop:
+  %iv = phi i64 [ 1, %entry ], [ %iv.next, %loop ]
+  %iv.next = add nuw i64 %iv, 1
+  call void @clobber()
+  %exitcond86.not.i.i = icmp eq i64 %iv, %N
+  br i1 %exitcond86.not.i.i, label %exit, label %loop
+
+exit:
+  ret void
+}
+
+define void @eq_exit_check_constant_ptr(ptr %start) {
+; CHECK-LABEL: @eq_exit_check_constant_ptr(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[UPPER:%.*]] = getelementptr inbounds i8, ptr [[START:%.*]], i8 2
+; CHECK-NEXT:    br label [[LOOP:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[IV:%.*]] = phi ptr [ [[START]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[IV_NEXT]] = getelementptr inbounds i8, ptr [[IV]], i8 1
+; CHECK-NEXT:    call void @clobber()
+; CHECK-NEXT:    [[C:%.*]] = icmp eq ptr [[IV]], [[UPPER]]
+; CHECK-NEXT:    br i1 [[C]], label [[EXIT:%.*]], label [[LOOP]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+entry:
+  %upper = getelementptr inbounds i8, ptr %start, i8 2
+  br label %loop
+
+loop:
+  %iv = phi ptr [ %start, %entry], [ %iv.next, %loop ]
+  %iv.next = getelementptr inbounds i8, ptr %iv, i8 1
+  call void @clobber()
+  %c = icmp eq ptr %iv, %upper
+  br i1 %c, label %exit, label %loop
+
+exit:
+  ret void
+}