1 files changed, 167 insertions, 0 deletions
diff --git a/test/Transforms/LICM/speculate.ll b/test/Transforms/LICM/speculate.ll
new file mode 100644
index 0000000..507b193
--- /dev/null
+++ b/test/Transforms/LICM/speculate.ll
@@ -0,0 +1,167 @@
+; RUN: opt -S -licm < %s | FileCheck %s
+
+; UDiv is safe to speculate if the denominator is known non-zero.
+
+; CHECK: @safe_udiv
+; CHECK:      %div = udiv i64 %x, %or
+; CHECK-NEXT: br label %for.body
+
+define void @safe_udiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
+entry:
+  %or = or i64 %m, 1
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.inc
+  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
+  %arrayidx = getelementptr inbounds i32* %p, i64 %i.02
+  %0 = load i32* %arrayidx, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %for.inc, label %if.then
+
+if.then:                                          ; preds = %for.body
+  %div = udiv i64 %x, %or
+  %arrayidx1 = getelementptr inbounds i64* %q, i64 %i.02
+  store i64 %div, i64* %arrayidx1, align 8
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %for.body
+  %inc = add i64 %i.02, 1
+  %cmp = icmp slt i64 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.inc, %entry
+  ret void
+}
+
+; UDiv is unsafe to speculate if the denominator is not known non-zero.
+
+; CHECK: @unsafe_udiv
+; CHECK-NOT:  udiv
+; CHECK: for.body:
+
+define void @unsafe_udiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.inc
+  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
+  %arrayidx = getelementptr inbounds i32* %p, i64 %i.02
+  %0 = load i32* %arrayidx, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %for.inc, label %if.then
+
+if.then:                                          ; preds = %for.body
+  %div = udiv i64 %x, %m
+  %arrayidx1 = getelementptr inbounds i64* %q, i64 %i.02
+  store i64 %div, i64* %arrayidx1, align 8
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %for.body
+  %inc = add i64 %i.02, 1
+  %cmp = icmp slt i64 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.inc, %entry
+  ret void
+}
+
+; SDiv is safe to speculate if the denominator is known non-zero and
+; known to have at least one zero bit.
+
+; CHECK: @safe_sdiv
+; CHECK:      %div = sdiv i64 %x, %or
+; CHECK-NEXT: br label %for.body
+
+define void @safe_sdiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
+entry:
+  %and = and i64 %m, -3
+  %or = or i64 %and, 1
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.inc
+  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
+  %arrayidx = getelementptr inbounds i32* %p, i64 %i.02
+  %0 = load i32* %arrayidx, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %for.inc, label %if.then
+
+if.then:                                          ; preds = %for.body
+  %div = sdiv i64 %x, %or
+  %arrayidx1 = getelementptr inbounds i64* %q, i64 %i.02
+  store i64 %div, i64* %arrayidx1, align 8
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %for.body
+  %inc = add i64 %i.02, 1
+  %cmp = icmp slt i64 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.inc, %entry
+  ret void
+}
+
+; SDiv is unsafe to speculate if the denominator is not known non-zero.
+
+; CHECK: @unsafe_sdiv_a
+; CHECK-NOT:  sdiv
+; CHECK: for.body:
+
+define void @unsafe_sdiv_a(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
+entry:
+  %or = or i64 %m, 1
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.inc
+  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
+  %arrayidx = getelementptr inbounds i32* %p, i64 %i.02
+  %0 = load i32* %arrayidx, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %for.inc, label %if.then
+
+if.then:                                          ; preds = %for.body
+  %div = sdiv i64 %x, %or
+  %arrayidx1 = getelementptr inbounds i64* %q, i64 %i.02
+  store i64 %div, i64* %arrayidx1, align 8
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %for.body
+  %inc = add i64 %i.02, 1
+  %cmp = icmp slt i64 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.inc, %entry
+  ret void
+}
+
+; SDiv is unsafe to speculate if the denominator is not known to have a zero bit.
+
+; CHECK: @unsafe_sdiv_b
+; CHECK-NOT:  sdiv
+; CHECK: for.body:
+
+define void @unsafe_sdiv_b(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
+entry:
+  %and = and i64 %m, -3
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.inc
+  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
+  %arrayidx = getelementptr inbounds i32* %p, i64 %i.02
+  %0 = load i32* %arrayidx, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %for.inc, label %if.then
+
+if.then:                                          ; preds = %for.body
+  %div = sdiv i64 %x, %and
+  %arrayidx1 = getelementptr inbounds i64* %q, i64 %i.02
+  store i64 %div, i64* %arrayidx1, align 8
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %for.body
+  %inc = add i64 %i.02, 1
+  %cmp = icmp slt i64 %inc, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.inc, %entry
+  ret void
+}