1 files changed, 57 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/2012-08-28-udiv_ashl.ll b/test/Transforms/InstCombine/2012-08-28-udiv_ashl.ll
new file mode 100644
index 0000000000..4efaf8c172
--- /dev/null
+++ b/test/Transforms/InstCombine/2012-08-28-udiv_ashl.ll
@@ -0,0 +1,57 @@
+; RUN: opt -S -instcombine < %s | FileCheck %s
+
+; rdar://12182093
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.8.0"
+
+; CHECK: @udiv400
+; CHECK: udiv i32 %x, 400
+; CHECK: ret
+define i32 @udiv400(i32 %x) {
+entry:
+  %div = lshr i32 %x, 2
+  %div1 = udiv i32 %div, 100
+  ret i32 %div1
+}
+
+
+; CHECK: @udiv400_no
+; CHECK: ashr
+; CHECK: div
+; CHECK: ret
+define i32 @udiv400_no(i32 %x) {
+entry:
+  %div = ashr i32 %x, 2
+  %div1 = udiv i32 %div, 100
+  ret i32 %div1
+}
+
+; CHECK: @sdiv400_yes
+; CHECK: udiv i32 %x, 400
+; CHECK: ret
+define i32 @sdiv400_yes(i32 %x) {
+entry:
+  %div = lshr i32 %x, 2
+  ; The sign bits of both operands are zero (i.e. we can prove they are
+  ; unsigned inputs), turn this into a udiv.
+  ; Next, optimize this just like sdiv.
+  %div1 = sdiv i32 %div, 100
+  ret i32 %div1
+}
+
+
+; CHECK: @udiv_i80
+; CHECK: udiv i80 %x, 400
+; CHECK: ret
+define i80 @udiv_i80(i80 %x) {
+  %div = lshr i80 %x, 2
+  %div1 = udiv i80 %div, 100
+  ret i80 %div1
+}
+
+define i32 @no_crash_notconst_udiv(i32 %x, i32 %notconst) {
+  %div = lshr i32 %x, %notconst
+  %div1 = udiv i32 %div, 100
+  ret i32 %div1
+}