[DAGCombiner] Preserve the exact bit when simplifying SRA to SRL.

[oota-llvm.git] / test / CodeGen / X86 / shift-combine.ll

diff --git a/test/CodeGen/X86/shift-combine.ll b/test/CodeGen/X86/shift-combine.ll
index 51f83036c23d05bfb8ffe0e4c8c2975ba369b131..43301041a0b6984fca48f49faf7a2f4c291a6fe0 100644 (file)
--- a/test/CodeGen/X86/shift-combine.ll
+++ b/test/CodeGen/X86/shift-combine.ll
@@ -3,7 +3,7 @@
 @array = weak global [4 x i32] zeroinitializer
 
 define i32 @test_lshr_and(i32 %x) {
-; CHECK: test_lshr_and:
+; CHECK-LABEL: test_lshr_and:
 ; CHECK-NOT: shrl
 ; CHECK: andl $12,
 ; CHECK: movl {{.*}}array{{.*}},
@@ -12,8 +12,67 @@ define i32 @test_lshr_and(i32 %x) {
 entry:
   %tmp2 = lshr i32 %x, 2
   %tmp3 = and i32 %tmp2, 3
-  %tmp4 = getelementptr [4 x i32]* @array, i32 0, i32 %tmp3
-  %tmp5 = load i32* %tmp4, align 4
+  %tmp4 = getelementptr [4 x i32], [4 x i32]* @array, i32 0, i32 %tmp3
+  %tmp5 = load i32, i32* %tmp4, align 4
   ret i32 %tmp5
 }
 
+define i32* @test_exact1(i32 %a, i32 %b, i32* %x)  {
+; CHECK-LABEL: test_exact1:
+; CHECK: sarl %
+
+  %sub = sub i32 %b, %a
+  %shr = ashr exact i32 %sub, 3
+  %gep = getelementptr inbounds i32, i32* %x, i32 %shr
+  ret i32* %gep
+}
+
+define i32* @test_exact2(i32 %a, i32 %b, i32* %x)  {
+; CHECK-LABEL: test_exact2:
+; CHECK: sarl %
+
+  %sub = sub i32 %b, %a
+  %shr = ashr exact i32 %sub, 3
+  %gep = getelementptr inbounds i32, i32* %x, i32 %shr
+  ret i32* %gep
+}
+
+define i32* @test_exact3(i32 %a, i32 %b, i32* %x)  {
+; CHECK-LABEL: test_exact3:
+; CHECK-NOT: sarl
+
+  %sub = sub i32 %b, %a
+  %shr = ashr exact i32 %sub, 2
+  %gep = getelementptr inbounds i32, i32* %x, i32 %shr
+  ret i32* %gep
+}
+
+define i32* @test_exact4(i32 %a, i32 %b, i32* %x)  {
+; CHECK-LABEL: test_exact4:
+; CHECK: shrl %
+
+  %sub = sub i32 %b, %a
+  %shr = lshr exact i32 %sub, 3
+  %gep = getelementptr inbounds i32, i32* %x, i32 %shr
+  ret i32* %gep
+}
+
+define i32* @test_exact5(i32 %a, i32 %b, i32* %x)  {
+; CHECK-LABEL: test_exact5:
+; CHECK: shrl %
+
+  %sub = sub i32 %b, %a
+  %shr = lshr exact i32 %sub, 3
+  %gep = getelementptr inbounds i32, i32* %x, i32 %shr
+  ret i32* %gep
+}
+
+define i32* @test_exact6(i32 %a, i32 %b, i32* %x)  {
+; CHECK-LABEL: test_exact6:
+; CHECK-NOT: shrl
+
+  %sub = sub i32 %b, %a
+  %shr = lshr exact i32 %sub, 2
+  %gep = getelementptr inbounds i32, i32* %x, i32 %shr
+  ret i32* %gep
+}