Add the llvm.frameallocate and llvm.recoverframeallocation intrinsics

These intrinsics allow multiple functions to share a single stack
allocation from one function's call frame. The function with the
allocation may only perform one allocation, and it must be in the entry
block.

Functions accessing the allocation call llvm.recoverframeallocation with
the function whose frame they are accessing and a frame pointer from an
active call frame of that function.

These intrinsics are very difficult to inline correctly, so the
intention is that they be introduced rarely, or at least very late
during EH preparation.

Reviewers: echristo, andrew.w.kaylor

Differential Revision: http://reviews.llvm.org/D6493

llvm-svn: 225746

1 files changed, 48 insertions, 0 deletions

diff --git a/llvm/test/Verifier/frameallocate.ll b/llvm/test/Verifier/frameallocate.ll
new file mode 100644
index 00000000000..3a4258007fd
--- /dev/null
+++ b/llvm/test/Verifier/frameallocate.ll
@@ -0,0 +1,48 @@
+; RUN: not llvm-as %s -o /dev/null 2>&1 | FileCheck %s
+
+declare i8* @llvm.frameallocate(i32)
+declare i8* @llvm.recoverframeallocation(i8*, i8*)
+
+define internal void @f() {
+  call i8* @llvm.frameallocate(i32 4)
+  call i8* @llvm.frameallocate(i32 4)
+  ret void
+}
+; CHECK: multiple calls to llvm.frameallocate in one function
+
+define internal void @f_a(i32 %n) {
+  call i8* @llvm.frameallocate(i32 %n)
+  ret void
+}
+; CHECK: llvm.frameallocate argument must be constant integer size
+
+define internal void @g() {
+entry:
+  br label %not_entry
+not_entry:
+  call i8* @llvm.frameallocate(i32 4)
+  ret void
+}
+; CHECK: llvm.frameallocate used outside of entry block
+
+define internal void @h() {
+  call i8* @llvm.recoverframeallocation(i8* null, i8* null)
+  ret void
+}
+; CHECK: llvm.recoverframeallocation first argument must be function defined in this module
+
+@global = constant i8 0
+
+declare void @declaration()
+
+define internal void @i() {
+  call i8* @llvm.recoverframeallocation(i8* @global, i8* null)
+  ret void
+}
+; CHECK: llvm.recoverframeallocation first argument must be function defined in this module
+
+define internal void @j() {
+  call i8* @llvm.recoverframeallocation(i8* bitcast(void()* @declaration to i8*), i8* null)
+  ret void
+}
+; CHECK: llvm.recoverframeallocation first argument must be function defined in this module