From ecdf45b1e6b37ec44681b5fc687f0c94578491af Mon Sep 17 00:00:00 2001
From: Nico Weber <nicolasweber@gmx.de>
Date: Thu, 14 Jul 2016 13:54:26 +0000
Subject: [PATCH] Teach fast isel calls and rets about stdcall.

stdcall is callee-pop like thiscall, so the thiscall changes already did most
of the work for this.  This change only opts stdcall in and adds tests.

llvm-svn: 275414
---
 llvm/lib/Target/X86/X86FastISel.cpp     |  2 ++
 llvm/test/CodeGen/X86/fast-isel-call.ll | 15 ++++++++++++++-
 llvm/test/CodeGen/X86/fast-isel-x86.ll  | 20 +++++++++++++++-----
 3 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/Target/X86/X86FastISel.cpp b/llvm/lib/Target/X86/X86FastISel.cpp
index 182731f..fae4527 100644
--- a/llvm/lib/Target/X86/X86FastISel.cpp
+++ b/llvm/lib/Target/X86/X86FastISel.cpp
@@ -1151,6 +1151,7 @@ bool X86FastISel::X86SelectRet(const Instruction *I) {
   if (CC != CallingConv::C &&
       CC != CallingConv::Fast &&
       CC != CallingConv::X86_FastCall &&
+      CC != CallingConv::X86_StdCall &&
       CC != CallingConv::X86_ThisCall &&
       CC != CallingConv::X86_64_SysV)
     return false;
@@ -3025,6 +3026,7 @@ bool X86FastISel::fastLowerCall(CallLoweringInfo &CLI) {
   case CallingConv::WebKit_JS:
   case CallingConv::Swift:
   case CallingConv::X86_FastCall:
+  case CallingConv::X86_StdCall:
   case CallingConv::X86_ThisCall:
   case CallingConv::X86_64_Win64:
   case CallingConv::X86_64_SysV:
diff --git a/llvm/test/CodeGen/X86/fast-isel-call.ll b/llvm/test/CodeGen/X86/fast-isel-call.ll
index 945fdf0..6823a0e 100644
--- a/llvm/test/CodeGen/X86/fast-isel-call.ll
+++ b/llvm/test/CodeGen/X86/fast-isel-call.ll
@@ -57,7 +57,7 @@ define void @test4(i8* %a, i8* %b) {
 
 ; STDERR-NOT: FastISel missed call:   call x86_thiscallcc void @thiscallfun
 %struct.S = type { i8 }
-define void @test5() #0 {
+define void @test5() {
 entry:
   %s = alloca %struct.S, align 1
 ; CHECK-LABEL: test5:
@@ -70,3 +70,16 @@ entry:
   ret void
 }
 declare x86_thiscallcc void @thiscallfun(%struct.S*, i32) #1
+
+; STDERR-NOT: FastISel missed call:   call x86_stdcallcc void @stdcallfun
+define void @test6() {
+entry:
+; CHECK-LABEL: test6:
+; CHECK: subl $12, %esp
+; CHECK: movl $43, (%esp)
+; CHECK: calll {{.*}}stdcallfun
+; CHECK: addl $8, %esp
+  call x86_stdcallcc void @stdcallfun(i32 43)
+  ret void
+}
+declare x86_stdcallcc void @stdcallfun(i32) #1
diff --git a/llvm/test/CodeGen/X86/fast-isel-x86.ll b/llvm/test/CodeGen/X86/fast-isel-x86.ll
index 64340bf..8cddee5 100644
--- a/llvm/test/CodeGen/X86/fast-isel-x86.ll
+++ b/llvm/test/CodeGen/X86/fast-isel-x86.ll
@@ -1,4 +1,5 @@
 ; RUN: llc -fast-isel -O0 -mcpu=generic -mtriple=i386-apple-darwin10 -relocation-model=pic < %s | FileCheck %s
+; RUN: llc -fast-isel -O0 -mcpu=generic -mtriple=i386-apple-darwin10 -relocation-model=pic < %s -fast-isel-verbose 2>&1 >/dev/null | FileCheck -check-prefix=STDERR -allow-empty %s
 
 ; This should use flds to set the return value.
 ; CHECK-LABEL: test0:
@@ -21,8 +22,9 @@ define void @test1({i32, i32, i32, i32}* sret %p) nounwind {
 ; This should pop 8 bytes on return.
 ; CHECK-LABEL: thiscallfun:
 ; CHECK: retl $8
-define x86_thiscallcc void @thiscallfun(i32* %this, i32 %a, i32 %b) nounwind {
-  ret void
+define x86_thiscallcc i32 @thiscallfun(i32* %this, i32 %a, i32 %b) nounwind {
+; STDERR-NOT: FastISel missed terminator: ret i32 12345
+  ret i32 12345
 }
 
 ; Here, the callee pop doesn't fit the 16 bit immediate -- see x86-big-ret.ll
@@ -36,11 +38,19 @@ define x86_thiscallcc void @thiscall_large(i32* %this, [65533 x i8]* byval %b) n
   ret void
 }
 
+; This should pop 4 bytes on return.
+; CHECK-LABEL: stdcallfun:
+; CHECK: retl $4
+define x86_stdcallcc i32 @stdcallfun(i32 %a) nounwind {
+; STDERR-NOT: FastISel missed terminator: ret i32 54321
+  ret i32 54321
+}
+
 ; Properly initialize the pic base.
 ; CHECK-LABEL: test2:
 ; CHECK-NOT: HHH
-; CHECK: call{{.*}}L4$pb
-; CHECK-NEXT: L4$pb:
+; CHECK: call{{.*}}L5$pb
+; CHECK-NEXT: L5$pb:
 ; CHECK-NEXT: pop
 ; CHECK: HHH
 ; CHECK: retl
@@ -93,7 +103,7 @@ entry:
 ; SDag-ISel's arg push:
 ; CHECK: movl %esp, [[REGISTER:%[a-z]+]]
 ; CHECK: movl $42, ([[REGISTER]])
-; CHECK: movl L_test5dllimport$non_lazy_ptr-L7$pb(%eax), %eax
+; CHECK: movl L_test5dllimport$non_lazy_ptr-L8$pb(%eax), %eax
 
 }
 declare dllimport i32 @test5dllimport(i32)
-- 
2.7.4