[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.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181204 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/SystemZ/asm-04.ll

@@ -0,0 +1,16 @@
+; Test the "T" asm constraint, which accepts addresses that have a base,
+; an index and a 20-bit displacement.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+define void @f1(i64 %base) {
+; CHECK: f1:
+; CHECK: blah 0(%r2)
+; CHECK: br %r14
+  %addr = inttoptr i64 %base to i64 *
+  call void asm "blah $0", "=*T" (i64 *%addr)
+  ret void
+}
+
+; FIXME: at the moment the precise constraint is not passed down to
+; target code, so we must conservatively treat "T" as "Q".