[llvm] 1ef3f83 - [NFC] [Coroutines] Add tests to address the problem for converting to musttail

[Chuanqi Xu via llvm-commits]

Author: Chuanqi Xu
Date: 2021-12-27T20:27:31+08:00
New Revision: 1ef3f83ef242d51ddce5d881e99d71bd8494a3e3

URL: https://github.com/llvm/llvm-project/commit/1ef3f83ef242d51ddce5d881e99d71bd8494a3e3
DIFF: https://github.com/llvm/llvm-project/commit/1ef3f83ef242d51ddce5d881e99d71bd8494a3e3.diff

LOG: [NFC] [Coroutines] Add tests to address the problem for converting to musttail
call

Add two tests to address the problem for missing oppotunities to convert
calls to musttail call.

Added: 
    llvm/test/Transforms/Coroutines/coro-split-musttail4.ll
    llvm/test/Transforms/Coroutines/coro-split-musttail5.ll

Modified: 
    

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/Coroutines/coro-split-musttail4.ll b/llvm/test/Transforms/Coroutines/coro-split-musttail4.ll
new file mode 100644
index 0000000000000..9fd8017996206
--- /dev/null
+++ b/llvm/test/Transforms/Coroutines/coro-split-musttail4.ll
@@ -0,0 +1,65 @@
+; Tests that coro-split will convert a call before coro.suspend to a musttail call
+; while the user of the coro.suspend is a icmpinst.
+; RUN: opt < %s -passes='cgscc(coro-split),simplifycfg,early-cse' -S | FileCheck %s
+
+define void @fakeresume1(i8*)  {
+entry:
+  ret void;
+}
+
+define void @f() #0 {
+entry:
+  %id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
+  %alloc = call i8* @malloc(i64 16) #3
+  %vFrame = call noalias nonnull i8* @llvm.coro.begin(token %id, i8* %alloc)
+
+  %save = call token @llvm.coro.save(i8* null)
+
+  %init_suspend = call i8 @llvm.coro.suspend(token %save, i1 false)
+  switch i8 %init_suspend, label %coro.end [
+    i8 0, label %await.ready
+    i8 1, label %coro.end
+  ]
+await.ready:
+  %save2 = call token @llvm.coro.save(i8* null)
+
+  call fastcc void @fakeresume1(i8* align 8 null)
+  %suspend = call i8 @llvm.coro.suspend(token %save2, i1 true)
+  %switch = icmp ult i8 %suspend, 2
+  br i1 %switch, label %cleanup, label %coro.end
+
+cleanup:
+  %free.handle = call i8* @llvm.coro.free(token %id, i8* %vFrame)
+  %.not = icmp eq i8* %free.handle, null
+  br i1 %.not, label %coro.end, label %coro.free
+
+coro.free:
+  call void @delete(i8* nonnull %free.handle) #2
+  br label %coro.end
+
+coro.end:
+  call i1 @llvm.coro.end(i8* null, i1 false)
+  ret void
+}
+
+; FIXME: The fakerresume1 here should be musttail call.
+; CHECK-LABEL: @f.resume(
+; CHECK-NOT: musttail call fastcc void @fakeresume1(
+
+declare token @llvm.coro.id(i32, i8* readnone, i8* nocapture readonly, i8*) #1
+declare i1 @llvm.coro.alloc(token) #2
+declare i64 @llvm.coro.size.i64() #3
+declare i8* @llvm.coro.begin(token, i8* writeonly) #2
+declare token @llvm.coro.save(i8*) #2
+declare i8* @llvm.coro.frame() #3
+declare i8 @llvm.coro.suspend(token, i1) #2
+declare i8* @llvm.coro.free(token, i8* nocapture readonly) #1
+declare i1 @llvm.coro.end(i8*, i1) #2
+declare i8* @llvm.coro.subfn.addr(i8* nocapture readonly, i8) #1
+declare i8* @malloc(i64)
+declare void @delete(i8* nonnull) #2
+
+attributes #0 = { "coroutine.presplit"="1" }
+attributes #1 = { argmemonly nounwind readonly }
+attributes #2 = { nounwind }
+attributes #3 = { nounwind readnone }

diff  --git a/llvm/test/Transforms/Coroutines/coro-split-musttail5.ll b/llvm/test/Transforms/Coroutines/coro-split-musttail5.ll
new file mode 100644
index 0000000000000..84a52e47f939d
--- /dev/null
+++ b/llvm/test/Transforms/Coroutines/coro-split-musttail5.ll
@@ -0,0 +1,62 @@
+; Tests that sinked lifetime markers wouldn't provent optimization
+; to convert a resuming call to a musttail call.
+; RUN: opt < %s -passes='cgscc(coro-split),simplifycfg,early-cse' -S | FileCheck %s
+
+declare void @fakeresume1(i64* align 8)
+
+define void @g() #0 {
+entry:
+  %id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
+  %alloc = call i8* @malloc(i64 16) #3
+  %alloc.var = alloca i8
+  call void @llvm.lifetime.start.p0i8(i64 1, i8* %alloc.var)
+  %vFrame = call noalias nonnull i8* @llvm.coro.begin(token %id, i8* %alloc)
+
+  %save = call token @llvm.coro.save(i8* null)
+  %suspend = call i8 @llvm.coro.suspend(token %save, i1 false)
+
+  switch i8 %suspend, label %exit [
+    i8 0, label %await.suspend
+    i8 1, label %exit
+  ]
+await.suspend:
+  %save2 = call token @llvm.coro.save(i8* null)
+  call fastcc void @fakeresume1(i64* align 8 null)
+  %suspend2 = call i8 @llvm.coro.suspend(token %save2, i1 false)
+  switch i8 %suspend2, label %exit [
+    i8 0, label %await.ready
+    i8 1, label %exit
+  ]
+await.ready:
+  call void @consume(i8* %alloc.var)
+  call void @llvm.lifetime.end.p0i8(i64 1, i8* %alloc.var)
+  br label %exit
+exit:
+  call i1 @llvm.coro.end(i8* null, i1 false)
+  ret void
+}
+
+; FIXME: The fakeresume1 here should be marked as musttail.
+; Verify that in the resume part resume call is marked with musttail.
+; CHECK-LABEL: @g.resume(
+; CHECK-NOT: musttail call fastcc void @fakeresume1(i64* align 8 null)
+
+declare token @llvm.coro.id(i32, i8* readnone, i8* nocapture readonly, i8*) #1
+declare i1 @llvm.coro.alloc(token) #2
+declare i64 @llvm.coro.size.i64() #3
+declare i8* @llvm.coro.begin(token, i8* writeonly) #2
+declare token @llvm.coro.save(i8*) #2
+declare i8* @llvm.coro.frame() #3
+declare i8 @llvm.coro.suspend(token, i1) #2
+declare i8* @llvm.coro.free(token, i8* nocapture readonly) #1
+declare i1 @llvm.coro.end(i8*, i1) #2
+declare i8* @llvm.coro.subfn.addr(i8* nocapture readonly, i8) #1
+declare i8* @malloc(i64)
+declare void @consume(i8*)
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
+
+attributes #0 = { "coroutine.presplit"="1" }
+attributes #1 = { argmemonly nounwind readonly }
+attributes #2 = { nounwind }
+attributes #3 = { nounwind readnone }