[tests] Precommit test for D103991

llvm/test/Analysis/ScalarEvolution/ne-overflow.ll

@@ -0,0 +1,187 @@
+
+; RUN: opt %s -analyze -scalar-evolution -enable-new-pm=0 -scalar-evolution-classify-expressions=0 2>&1 | FileCheck %s
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; A collection of tests focused on exercising logic to prove no-unsigned wrap
+; from mustprogress semantics of loops.
+
+; CHECK: Determining loop execution counts for: @test
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_preinc
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_well_defined_infinite_st
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_well_defined_infinite_ld
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_no_mustprogress
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_1024
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_uneven_divide
+; CHECK: Loop %for.body: backedge-taken count is (-1 + (-1431655765 * %N))
+; CHECK: Determining loop execution counts for: @test_non_invariant_rhs
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_abnormal_exit
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Determining loop execution counts for: @test_other_exit
+; CHECK: Loop %for.body: <multiple exits> Unpredictable backedge-taken count.
+
+define void @test(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+define void @test_preinc(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  %cmp = icmp ne i32 %iv, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+
+}
+
+@G = external global i32
+
+define void @test_well_defined_infinite_st(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  store volatile i32 0, i32* @G
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+define void @test_well_defined_infinite_ld(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  %val = load volatile i32, i32* @G
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+define void @test_no_mustprogress(i32 %N) {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+
+}
+
+
+define void @test_1024(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 1024
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+define void @test_uneven_divide(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 3
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+define void @test_non_invariant_rhs() mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  %N = load i32, i32* @G
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+declare void @mayexit()
+
+define void @test_abnormal_exit(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.body ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  call void @mayexit()
+  %cmp = icmp ne i32 %iv.next, %N
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+
+define void @test_other_exit(i32 %N) mustprogress {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i32 [ %iv.next, %for.latch ], [ 0, %entry ]
+  %iv.next = add i32 %iv, 2
+  %cmp1 = icmp ne i32 %iv.next, 20
+  br i1 %cmp1, label %for.latch, label %for.cond.cleanup
+
+for.latch:
+  %cmp2 = icmp ne i32 %iv.next, %N
+  br i1 %cmp2, label %for.body, label %for.cond.cleanup
+
+for.cond.cleanup:
+  ret void
+}
+
+