1 files changed, 140 insertions, 9 deletions
diff --git a/llvm/test/Transforms/Inline/inline-tail.ll b/llvm/test/Transforms/Inline/inline-tail.ll
index 8bb059d01a0..565491adf5b 100644
--- a/llvm/test/Transforms/Inline/inline-tail.ll
+++ b/llvm/test/Transforms/Inline/inline-tail.ll
@@ -1,15 +1,146 @@
-; RUN: opt < %s -inline -S | not grep tail
+; RUN: opt < %s -inline -S | FileCheck %s
 
-declare void @bar(i32*)
+; We have to apply the less restrictive TailCallKind of the call site being
+; inlined and any call sites cloned into the caller.
 
-define internal void @foo(i32* %P) {
-        tail call void @bar( i32* %P )
-        ret void
+; No tail marker after inlining, since test_capture_c captures an alloca.
+; CHECK: define void @test_capture_a(
+; CHECK-NOT: tail
+; CHECK: call void @test_capture_c(
+
+declare void @test_capture_c(i32*)
+define internal void @test_capture_b(i32* %P) {
+  tail call void @test_capture_c(i32* %P)
+  ret void
+}
+define void @test_capture_a() {
+  %A = alloca i32  		; captured by test_capture_b
+  call void @test_capture_b(i32* %A)
+  ret void
+}
+
+; No musttail marker after inlining, since the prototypes don't match.
+; CHECK: define void @test_proto_mismatch_a(
+; CHECK-NOT: musttail
+; CHECK: call void @test_proto_mismatch_c(
+
+declare void @test_proto_mismatch_c(i32*)
+define internal void @test_proto_mismatch_b(i32* %p) {
+  musttail call void @test_proto_mismatch_c(i32* %p)
+  ret void
+}
+define void @test_proto_mismatch_a() {
+  call void @test_proto_mismatch_b(i32* null)
+  ret void
 }
 
-define void @caller() {
-        %A = alloca i32         ; <i32*> [#uses=1]
-        call void @foo( i32* %A )
-        ret void
+; After inlining through a musttail call site, we need to keep musttail markers
+; to prevent unbounded stack growth.
+; CHECK: define void @test_musttail_basic_a(
+; CHECK: musttail call void @test_musttail_basic_c(
+
+declare void @test_musttail_basic_c(i32* %p)
+define internal void @test_musttail_basic_b(i32* %p) {
+  musttail call void @test_musttail_basic_c(i32* %p)
+  ret void
+}
+define void @test_musttail_basic_a(i32* %p) {
+  musttail call void @test_musttail_basic_b(i32* %p)
+  ret void
+}
+
+; We can't merge the returns.
+; CHECK: define void @test_multiret_a(
+; CHECK: musttail call void @test_multiret_c(
+; CHECK-NEXT: ret void
+; CHECK: musttail call void @test_multiret_d(
+; CHECK-NEXT: ret void
+
+declare void @test_multiret_c(i1 zeroext %b)
+declare void @test_multiret_d(i1 zeroext %b)
+define internal void @test_multiret_b(i1 zeroext %b) {
+  br i1 %b, label %c, label %d
+c:
+  musttail call void @test_multiret_c(i1 zeroext %b)
+  ret void
+d:
+  musttail call void @test_multiret_d(i1 zeroext %b)
+  ret void
+}
+define void @test_multiret_a(i1 zeroext %b) {
+  musttail call void @test_multiret_b(i1 zeroext %b)
+  ret void
 }
 
+; We have to avoid bitcast chains.
+; CHECK: define i32* @test_retptr_a(
+; CHECK: musttail call i8* @test_retptr_c(
+; CHECK-NEXT: bitcast i8* {{.*}} to i32*
+; CHECK-NEXT: ret i32*
+
+declare i8* @test_retptr_c()
+define internal i16* @test_retptr_b() {
+  %rv = musttail call i8* @test_retptr_c()
+  %v = bitcast i8* %rv to i16*
+  ret i16* %v
+}
+define i32* @test_retptr_a() {
+  %rv = musttail call i16* @test_retptr_b()
+  %v = bitcast i16* %rv to i32*
+  ret i32* %v
+}
+
+; Combine the last two cases: multiple returns with pointer bitcasts.
+; CHECK: define i32* @test_multiptrret_a(
+; CHECK: musttail call i8* @test_multiptrret_c(
+; CHECK-NEXT: bitcast i8* {{.*}} to i32*
+; CHECK-NEXT: ret i32*
+; CHECK: musttail call i8* @test_multiptrret_d(
+; CHECK-NEXT: bitcast i8* {{.*}} to i32*
+; CHECK-NEXT: ret i32*
+
+declare i8* @test_multiptrret_c(i1 zeroext %b)
+declare i8* @test_multiptrret_d(i1 zeroext %b)
+define internal i16* @test_multiptrret_b(i1 zeroext %b) {
+  br i1 %b, label %c, label %d
+c:
+  %c_rv = musttail call i8* @test_multiptrret_c(i1 zeroext %b)
+  %c_v = bitcast i8* %c_rv to i16*
+  ret i16* %c_v
+d:
+  %d_rv = musttail call i8* @test_multiptrret_d(i1 zeroext %b)
+  %d_v = bitcast i8* %d_rv to i16*
+  ret i16* %d_v
+}
+define i32* @test_multiptrret_a(i1 zeroext %b) {
+  %rv = musttail call i16* @test_multiptrret_b(i1 zeroext %b)
+  %v = bitcast i16* %rv to i32*
+  ret i32* %v
+}
+
+; Inline a musttail call site which contains a normal return and a musttail call.
+; CHECK: define i32 @test_mixedret_a(
+; CHECK: br i1 %b
+; CHECK: musttail call i32 @test_mixedret_c(
+; CHECK-NEXT: ret i32
+; CHECK: call i32 @test_mixedret_d(i1 zeroext %b)
+; CHECK: add i32 1,
+; CHECK-NOT: br
+; CHECK: ret i32
+
+declare i32 @test_mixedret_c(i1 zeroext %b)
+declare i32 @test_mixedret_d(i1 zeroext %b)
+define internal i32 @test_mixedret_b(i1 zeroext %b) {
+  br i1 %b, label %c, label %d
+c:
+  %c_rv = musttail call i32 @test_mixedret_c(i1 zeroext %b)
+  ret i32 %c_rv
+d:
+  %d_rv = call i32 @test_mixedret_d(i1 zeroext %b)
+  %d_rv1 = add i32 1, %d_rv
+  ret i32 %d_rv1
+}
+define i32 @test_mixedret_a(i1 zeroext %b) {
+  %rv = musttail call i32 @test_mixedret_b(i1 zeroext %b)
+  ret i32 %rv
+}