2 files changed, 52 insertions, 2 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 0000000..9f52119
--- /dev/null
+++ b/test/Transforms/InstCombine/2012-08-28-udiv_ashl.ll
@@ -0,0 +1,50 @@
+; 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: @sdiv400
+; CHECK: sdiv i32 %x, 400
+; CHECK: ret
+define i32 @sdiv400(i32 %x) {
+entry:
+  %div = ashr i32 %x, 2
+  %div1 = sdiv 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
+}
diff --git a/test/Transforms/InstCombine/udiv-simplify-bug-1.ll b/test/Transforms/InstCombine/udiv-simplify-bug-1.ll
index d95e8f8..74f2fdd 100644
--- a/test/Transforms/InstCombine/udiv-simplify-bug-1.ll
+++ b/test/Transforms/InstCombine/udiv-simplify-bug-1.ll
@@ -6,9 +6,9 @@
 ; The udiv instructions shouldn't be optimized away, and the
 ; sext instructions should be optimized to zext.
 
-define i64 @bar(i32 %x) nounwind {
+define i64 @bar(i32 %x, i32 %g) nounwind {
   %y = lshr i32 %x, 30
-  %r = udiv i32 %y, 3
+  %r = udiv i32 %y, %g
   %z = sext i32 %r to i64
   ret i64 %z
 }