llvm-mirror/test/Transforms/Coroutines/ex2.ll
Gor Nishanov cc3ff9c81d [Coroutines] Part 9: Add cleanup subfunction.
Summary:
[Coroutines] Part 9: Add cleanup subfunction.

This patch completes coroutine heap allocation elision. Now, the heap elision example from docs\Coroutines.rst compiles and produces expected result (see test/Transform/Coroutines/ex3.ll)

Intrinsic Changes:
* coro.free gets a token parameter tying it to coro.id to allow reliably discovering all coro.frees associated with a particular coroutine.
* coro.id gets an extra parameter that points back to a coroutine function. This allows to check whether a coro.id describes the enclosing function or it belongs to a different function that was later inlined.

CoroSplit now creates three subfunctions:
# f$resume - resume logic
# f$destroy - cleanup logic, followed by a deallocation code
# f$cleanup - just the cleanup code

CoroElide pass during devirtualization replaces coro.destroy with either f$destroy or f$cleanup depending whether heap elision is performed or not.

Other fixes, improvements:
* Fixed buglet in Shape::buildFrame that was not creating coro.save properly if coroutine has more than one suspend point.

* Switched to using variable width suspend index field (no longer limited to 32 bit index field can be as little as i1 or as large as i<whatever-size_t-is>)

Reviewers: majnemer

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D23844

llvm-svn: 279971
2016-08-29 14:34:12 +00:00

64 lines
1.9 KiB
LLVM

; Second example from Doc/Coroutines.rst (custom alloc and free functions)
; RUN: opt < %s -O2 -enable-coroutines -S | FileCheck %s
define i8* @f(i32 %n) {
entry:
%id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
%need.dyn.alloc = call i1 @llvm.coro.alloc(token %id)
br i1 %need.dyn.alloc, label %dyn.alloc, label %coro.begin
dyn.alloc:
%size = call i32 @llvm.coro.size.i32()
%alloc = call i8* @CustomAlloc(i32 %size)
br label %coro.begin
coro.begin:
%phi = phi i8* [ null, %entry ], [ %alloc, %dyn.alloc ]
%hdl = call noalias i8* @llvm.coro.begin(token %id, i8* %phi)
br label %loop
loop:
%n.val = phi i32 [ %n, %coro.begin ], [ %inc, %loop ]
%inc = add nsw i32 %n.val, 1
call void @print(i32 %n.val)
%0 = call i8 @llvm.coro.suspend(token none, i1 false)
switch i8 %0, label %suspend [i8 0, label %loop
i8 1, label %cleanup]
cleanup:
%mem = call i8* @llvm.coro.free(token %id, i8* %hdl)
%need.dyn.free = icmp ne i8* %mem, null
br i1 %need.dyn.free, label %dyn.free, label %suspend
dyn.free:
call void @CustomFree(i8* %mem)
br label %suspend
suspend:
call void @llvm.coro.end(i8* %hdl, i1 false)
ret i8* %hdl
}
; CHECK-LABEL: @main
define i32 @main() {
entry:
%hdl = call i8* @f(i32 4)
call void @llvm.coro.resume(i8* %hdl)
call void @llvm.coro.resume(i8* %hdl)
call void @llvm.coro.destroy(i8* %hdl)
ret i32 0
; CHECK: call void @print(i32 4)
; CHECK-NEXT: call void @print(i32 5)
; CHECK-NEXT: call void @print(i32 6)
; CHECK-NEXT: ret i32 0
}
declare i8* @CustomAlloc(i32)
declare void @CustomFree(i8*)
declare void @print(i32)
declare token @llvm.coro.id(i32, i8*, i8*, i8*)
declare i1 @llvm.coro.alloc(token)
declare i32 @llvm.coro.size.i32()
declare i8* @llvm.coro.begin(token, i8*)
declare i8 @llvm.coro.suspend(token, i1)
declare i8* @llvm.coro.free(token, i8*)
declare void @llvm.coro.end(i8*, i1)
declare void @llvm.coro.resume(i8*)
declare void @llvm.coro.destroy(i8*)