From 8d66df15f4b57357819426a8bce67e9332cf9c9a Mon Sep 17 00:00:00 2001
From: Nico Weber <nicolasweber@gmx.de>
Date: Fri, 15 Jul 2016 20:18:37 +0000
Subject: [PATCH] Teach fast isel about the win64 calling convention.

This mostly just works.

Vectorcall rets are still not supported.

The win64_eh test change is because fast isel doesn't use rsi for temporary
computations, so it doesn't need to be pushed. The test case I'm changing was
originally added to test pushes, but by now there are other test cases in that
file exercising that code path.

https://reviews.llvm.org/D22422

llvm-svn: 275607
---
 llvm/lib/Target/X86/X86FastISel.cpp       | 6 ++----
 llvm/test/CodeGen/X86/fast-isel-x86-64.ll | 8 ++++++++
 llvm/test/CodeGen/X86/win64_eh.ll         | 4 ----
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/llvm/lib/Target/X86/X86FastISel.cpp b/llvm/lib/Target/X86/X86FastISel.cpp
index fae4527..dfe3c80 100644
--- a/llvm/lib/Target/X86/X86FastISel.cpp
+++ b/llvm/lib/Target/X86/X86FastISel.cpp
@@ -1153,10 +1153,8 @@ bool X86FastISel::X86SelectRet(const Instruction *I) {
       CC != CallingConv::X86_FastCall &&
       CC != CallingConv::X86_StdCall &&
       CC != CallingConv::X86_ThisCall &&
-      CC != CallingConv::X86_64_SysV)
-    return false;
-
-  if (Subtarget->isCallingConvWin64(CC))
+      CC != CallingConv::X86_64_SysV &&
+      CC != CallingConv::X86_64_Win64)
     return false;
 
   // Don't handle popping bytes if they don't fit the ret's immediate.
diff --git a/llvm/test/CodeGen/X86/fast-isel-x86-64.ll b/llvm/test/CodeGen/X86/fast-isel-x86-64.ll
index d748cba..ad0f11f 100644
--- a/llvm/test/CodeGen/X86/fast-isel-x86-64.ll
+++ b/llvm/test/CodeGen/X86/fast-isel-x86-64.ll
@@ -1,4 +1,5 @@
 ; RUN: llc < %s -mattr=-avx -fast-isel -mcpu=core2 -O0 -regalloc=fast -asm-verbose=0 -fast-isel-abort=1 | FileCheck %s
+; RUN: llc < %s -mattr=-avx -fast-isel -mcpu=core2 -O0 -regalloc=fast -asm-verbose=0 -fast-isel-verbose 2>&1 >/dev/null | FileCheck %s --check-prefix=STDERR --allow-empty
 ; RUN: llc < %s -mattr=+avx -fast-isel -mcpu=core2 -O0 -regalloc=fast -asm-verbose=0 -fast-isel-abort=1 | FileCheck %s --check-prefix=AVX
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
@@ -312,3 +313,10 @@ define void @allocamaterialize() {
   call void @takesi32ptr(i32* %a)
   ret void
 }
+
+; STDERR-NOT: FastISel missed terminator:   ret void
+; CHECK-LABEL: win64ccfun
+define x86_64_win64cc void @win64ccfun(i32 %i) {
+; CHECK: ret
+  ret void
+}
diff --git a/llvm/test/CodeGen/X86/win64_eh.ll b/llvm/test/CodeGen/X86/win64_eh.ll
index cb9d026..9421f00 100644
--- a/llvm/test/CodeGen/X86/win64_eh.ll
+++ b/llvm/test/CodeGen/X86/win64_eh.ll
@@ -47,7 +47,6 @@ entry:
 ; WIN64: .seh_endproc
 
 
-; Checks stack push
 define i32 @foo3(i32 %f_arg, i32 %e_arg, i32 %d_arg, i32 %c_arg, i32 %b_arg, i32 %a_arg) uwtable {
 entry:
   %a = alloca i32
@@ -83,14 +82,11 @@ entry:
 }
 ; WIN64-LABEL: foo3:
 ; WIN64: .seh_proc foo3
-; WIN64: pushq %rsi
-; WIN64: .seh_pushreg 6
 ; NORM:  subq $24, %rsp
 ; ATOM:  leaq -24(%rsp), %rsp
 ; WIN64: .seh_stackalloc 24
 ; WIN64: .seh_endprologue
 ; WIN64: addq $24, %rsp
-; WIN64: popq %rsi
 ; WIN64: ret
 ; WIN64: .seh_endproc
 
-- 
2.7.4