ARM64: initial backend import

This adds a second implementation of the AArch64 architecture to LLVM,
accessible in parallel via the "arm64" triple. The plan over the
coming weeks & months is to merge the two into a single backend,
during which time thorough code review should naturally occur.

Everything will be easier with the target in-tree though, hence this
commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205090 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 27 insertions, 0 deletions

diff --git a/test/CodeGen/ARM64/regress-f128csel-flags.ll b/test/CodeGen/ARM64/regress-f128csel-flags.ll
new file mode 100644
index 0000000000..a1daf03f4f
--- /dev/null
+++ b/test/CodeGen/ARM64/regress-f128csel-flags.ll
@@ -0,0 +1,27 @@
+; RUN: llc -march=arm64 -verify-machineinstrs < %s | FileCheck %s
+
+; We used to not mark NZCV as being used in the continuation basic-block
+; when lowering a 128-bit "select" to branches. This meant a subsequent use
+; of the same flags gave an internal fault here.
+
+declare void @foo(fp128)
+
+define double @test_f128csel_flags(i32 %lhs, fp128 %a, fp128 %b, double %l, double %r) nounwind {
+; CHECK: test_f128csel_flags
+
+    %tst = icmp ne i32 %lhs, 42
+    %val = select i1 %tst, fp128 %a, fp128 %b
+; CHECK: cmp w0, #42
+; CHECK: b.eq {{.?LBB0}}
+
+    call void @foo(fp128 %val)
+    %retval = select i1 %tst, double %l, double %r
+
+    ; It's also reasonably important that the actual fcsel comes before the
+    ; function call since bl may corrupt NZCV. We were doing the right thing anyway,
+    ; but just as well test it while we're here.
+; CHECK: fcsel {{d[0-9]+}}, {{d[0-9]+}}, {{d[0-9]+}}, ne
+; CHECK: bl {{_?foo}}
+
+    ret double %retval
+}