Enable sibling call optimization of libcalls which are expanded during

legalization time. Since at legalization time there is no mapping from
SDNode back to the corresponding LLVM instruction and the return
SDNode is target specific, this requires a target hook to check for
eligibility. Only x86 and ARM support this form of sibcall optimization
right now.
rdar://8707777


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120501 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 24 insertions, 0 deletions

diff --git a/test/CodeGen/X86/sibcall-5.ll b/test/CodeGen/X86/sibcall-5.ll
new file mode 100644
index 0000000..4a2e7fb
--- /dev/null
+++ b/test/CodeGen/X86/sibcall-5.ll
@@ -0,0 +1,24 @@
+; RUN: llc < %s -march=x86-64 | FileCheck %s
+
+; Sibcall optimization of expanded libcalls.
+; rdar://8707777
+
+define double @foo(double %a) nounwind readonly ssp {
+entry:
+; CHECK: foo:
+; CHECK: jmp {{_?}}sin
+  %0 = tail call double @sin(double %a) nounwind readonly
+  ret double %0
+}
+
+define float @bar(float %a) nounwind readonly ssp {
+; CHECK: bar:
+; CHECK: jmp {{_?}}sinf
+entry:
+  %0 = tail call float @sinf(float %a) nounwind readonly
+  ret float %0
+}
+
+declare float @sinf(float) nounwind readonly
+
+declare double @sin(double) nounwind readonly