1 files changed, 90 insertions, 0 deletions
diff --git a/test/CodeGen/X86/musttail.ll b/test/CodeGen/X86/musttail.ll
new file mode 100644
index 0000000..ca5d311
--- /dev/null
+++ b/test/CodeGen/X86/musttail.ll
@@ -0,0 +1,90 @@
+; RUN: llc -march=x86 < %s | FileCheck %s
+; RUN: llc -march=x86 -O0 < %s | FileCheck %s
+; RUN: llc -march=x86 -disable-tail-calls < %s | FileCheck %s
+
+declare void @t1_callee(i8*)
+define void @t1(i32* %a) {
+; CHECK-LABEL: t1:
+; CHECK: jmp {{_?}}t1_callee
+  %b = bitcast i32* %a to i8*
+  musttail call void @t1_callee(i8* %b)
+  ret void
+}
+
+declare i8* @t2_callee()
+define i32* @t2() {
+; CHECK-LABEL: t2:
+; CHECK: jmp {{_?}}t2_callee
+  %v = musttail call i8* @t2_callee()
+  %w = bitcast i8* %v to i32*
+  ret i32* %w
+}
+
+; Complex frame layout: stack realignment with dynamic alloca.
+define void @t3(i32 %n) alignstack(32) nounwind {
+entry:
+; CHECK: t3:
+; CHECK: pushl %ebp
+; CHECK: pushl %esi
+; CHECK: andl $-32, %esp
+; CHECK: movl %esp, %esi
+; CHECK: popl %esi
+; CHECK: popl %ebp
+; CHECK-NEXT: jmp {{_?}}t3_callee
+  %a = alloca i8, i32 %n
+  call void @capture(i8* %a)
+  musttail call void @t3_callee(i32 %n) nounwind
+  ret void
+}
+
+declare void @capture(i8*)
+declare void @t3_callee(i32)
+
+; Test that we actually copy in and out stack arguments that aren't forwarded
+; without modification.
+define i32 @t4({}* %fn, i32 %n, i32 %r) {
+; CHECK-LABEL: t4:
+; CHECK: incl %[[r:.*]]
+; CHECK: decl %[[n:.*]]
+; CHECK: movl %[[r]], {{[0-9]+}}(%esp)
+; CHECK: movl %[[n]], {{[0-9]+}}(%esp)
+; CHECK: jmpl *%{{.*}}
+
+entry:
+  %r1 = add i32 %r, 1
+  %n1 = sub i32 %n, 1
+  %fn_cast = bitcast {}* %fn to i32 ({}*, i32, i32)*
+  %r2 = musttail call i32 %fn_cast({}* %fn, i32 %n1, i32 %r1)
+  ret i32 %r2
+}
+
+; Combine the complex stack frame with the parameter modification.
+define i32 @t5({}* %fn, i32 %n, i32 %r) alignstack(32) {
+; CHECK-LABEL: t5:
+; CHECK: pushl %ebp
+; CHECK: movl %esp, %ebp
+; CHECK: pushl %esi
+; 	Align the stack.
+; CHECK: andl $-32, %esp
+; CHECK: movl %esp, %esi
+; 	Modify the args.
+; CHECK: incl %[[r:.*]]
+; CHECK: decl %[[n:.*]]
+; 	Store them through ebp, since that's the only stable arg pointer.
+; CHECK: movl %[[r]], {{[0-9]+}}(%ebp)
+; CHECK: movl %[[n]], {{[0-9]+}}(%ebp)
+; 	Epilogue.
+; CHECK: leal {{[-0-9]+}}(%ebp), %esp
+; CHECK: popl %esi
+; CHECK: popl %ebp
+; CHECK: jmpl *%{{.*}}
+
+entry:
+  %a = alloca i8, i32 %n
+  call void @capture(i8* %a)
+  %r1 = add i32 %r, 1
+  %n1 = sub i32 %n, 1
+  %fn_cast = bitcast {}* %fn to i32 ({}*, i32, i32)*
+  %r2 = musttail call i32 %fn_cast({}* %fn, i32 %n1, i32 %r1)
+  ret i32 %r2
+}