[SystemZ] Add CodeGen test cases

This adds all CodeGen tests for the SystemZ target.

This version of the patch incorporates feedback from a review by
Sean Silva.  Thanks to all reviewers!

Patch by Richard Sandiford.

llvm-svn: 181204
diff --git a/llvm/test/CodeGen/SystemZ/int-mul-05.ll b/llvm/test/CodeGen/SystemZ/int-mul-05.ll
new file mode 100644
index 0000000..5e4031b
--- /dev/null
+++ b/llvm/test/CodeGen/SystemZ/int-mul-05.ll
@@ -0,0 +1,159 @@
+; Test 32-bit multiplication in which the second operand is constant.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+; Check multiplication by 2, which should use shifts.
+define i32 @f1(i32 %a, i32 *%dest) {
+; CHECK: f1:
+; CHECK: sll %r2, 1
+; CHECK: br %r14
+  %mul = mul i32 %a, 2
+  ret i32 %mul
+}
+
+; Check multiplication by 3.
+define i32 @f2(i32 %a, i32 *%dest) {
+; CHECK: f2:
+; CHECK: mhi %r2, 3
+; CHECK: br %r14
+  %mul = mul i32 %a, 3
+  ret i32 %mul
+}
+
+; Check the high end of the MHI range.
+define i32 @f3(i32 %a, i32 *%dest) {
+; CHECK: f3:
+; CHECK: mhi %r2, 32767
+; CHECK: br %r14
+  %mul = mul i32 %a, 32767
+  ret i32 %mul
+}
+
+; Check the next value up, which should use shifts.
+define i32 @f4(i32 %a, i32 *%dest) {
+; CHECK: f4:
+; CHECK: sll %r2, 15
+; CHECK: br %r14
+  %mul = mul i32 %a, 32768
+  ret i32 %mul
+}
+
+; Check the next value up again, which can use MSFI.
+define i32 @f5(i32 %a, i32 *%dest) {
+; CHECK: f5:
+; CHECK: msfi %r2, 32769
+; CHECK: br %r14
+  %mul = mul i32 %a, 32769
+  ret i32 %mul
+}
+
+; Check the high end of the MSFI range.
+define i32 @f6(i32 %a, i32 *%dest) {
+; CHECK: f6:
+; CHECK: msfi %r2, 2147483647
+; CHECK: br %r14
+  %mul = mul i32 %a, 2147483647
+  ret i32 %mul
+}
+
+; Check the next value up, which should use shifts.
+define i32 @f7(i32 %a, i32 *%dest) {
+; CHECK: f7:
+; CHECK: sll %r2, 31
+; CHECK: br %r14
+  %mul = mul i32 %a, 2147483648
+  ret i32 %mul
+}
+
+; Check the next value up again, which is treated as a negative value.
+define i32 @f8(i32 %a, i32 *%dest) {
+; CHECK: f8:
+; CHECK: msfi %r2, -2147483647
+; CHECK: br %r14
+  %mul = mul i32 %a, 2147483649
+  ret i32 %mul
+}
+
+; Check multiplication by -1, which is a negation.
+define i32 @f9(i32 %a, i32 *%dest) {
+; CHECK: f9:
+; CHECK: lcr %r2, %r2
+; CHECK: br %r14
+  %mul = mul i32 %a, -1
+  ret i32 %mul
+}
+
+; Check multiplication by -2, which should use shifts.
+define i32 @f10(i32 %a, i32 *%dest) {
+; CHECK: f10:
+; CHECK: sll %r2, 1
+; CHECK: lcr %r2, %r2
+; CHECK: br %r14
+  %mul = mul i32 %a, -2
+  ret i32 %mul
+}
+
+; Check multiplication by -3.
+define i32 @f11(i32 %a, i32 *%dest) {
+; CHECK: f11:
+; CHECK: mhi %r2, -3
+; CHECK: br %r14
+  %mul = mul i32 %a, -3
+  ret i32 %mul
+}
+
+; Check the lowest useful MHI value.
+define i32 @f12(i32 %a, i32 *%dest) {
+; CHECK: f12:
+; CHECK: mhi %r2, -32767
+; CHECK: br %r14
+  %mul = mul i32 %a, -32767
+  ret i32 %mul
+}
+
+; Check the next value down, which should use shifts.
+define i32 @f13(i32 %a, i32 *%dest) {
+; CHECK: f13:
+; CHECK: sll %r2, 15
+; CHECK: lcr %r2, %r2
+; CHECK: br %r14
+  %mul = mul i32 %a, -32768
+  ret i32 %mul
+}
+
+; Check the next value down again, which can use MSFI.
+define i32 @f14(i32 %a, i32 *%dest) {
+; CHECK: f14:
+; CHECK: msfi %r2, -32769
+; CHECK: br %r14
+  %mul = mul i32 %a, -32769
+  ret i32 %mul
+}
+
+; Check the lowest useful MSFI value.
+define i32 @f15(i32 %a, i32 *%dest) {
+; CHECK: f15:
+; CHECK: msfi %r2, -2147483647
+; CHECK: br %r14
+  %mul = mul i32 %a, -2147483647
+  ret i32 %mul
+}
+
+; Check the next value down, which should use shifts.
+define i32 @f16(i32 %a, i32 *%dest) {
+; CHECK: f16:
+; CHECK: sll %r2, 31
+; CHECK-NOT: lcr
+; CHECK: br %r14
+  %mul = mul i32 %a, -2147483648
+  ret i32 %mul
+}
+
+; Check the next value down again, which is treated as a positive value.
+define i32 @f17(i32 %a, i32 *%dest) {
+; CHECK: f17:
+; CHECK: msfi %r2, 2147483647
+; CHECK: br %r14
+  %mul = mul i32 %a, -2147483649
+  ret i32 %mul
+}