Support segmented stacks on 64-bit FreeBSD.

This patch uses tcb_spare field in the tcb structure to store info.
Patch by Jyun-Yan You.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148041 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 60 insertions, 2 deletions

diff --git a/lib/Target/X86/X86FrameLowering.cpp b/lib/Target/X86/X86FrameLowering.cpp
index 639f5c2055..e5f6752614 100644
--- a/lib/Target/X86/X86FrameLowering.cpp
+++ b/lib/Target/X86/X86FrameLowering.cpp
@@ -1357,8 +1357,9 @@ X86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const {
 
   if (MF.getFunction()->isVarArg())
     report_fatal_error("Segmented stacks do not support vararg functions.");
-  if (!ST->isTargetLinux() && !ST->isTargetDarwin() && !ST->isTargetWin32())
-    report_fatal_error("Segmented stacks supported only on linux, darwin and win32.");
+  if (!ST->isTargetLinux() && !ST->isTargetDarwin() &&
+      !ST->isTargetWin32() && !ST->isTargetFreeBSD())
+    report_fatal_error("Segmented stacks not supported on this platform.");
 
   MachineBasicBlock *allocMBB = MF.CreateMachineBasicBlock();
   MachineBasicBlock *checkMBB = MF.CreateMachineBasicBlock();
@@ -1401,6 +1402,9 @@ X86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const {
     } else if (ST->isTargetDarwin()) {
       TlsReg = X86::GS;
       TlsOffset = 0x60 + 90*8; // See pthread_machdep.h. Steal TLS slot 90.
+    } else if (ST->isTargetFreeBSD()) {
+      TlsReg = X86::FS;
+      TlsOffset = 0x18;
     } else {
       report_fatal_error("Segmented stacks not supported on this platform.");
     }
@@ -1423,6 +1427,8 @@ X86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const {
     } else if (ST->isTargetWin32()) {
       TlsReg = X86::FS;
       TlsOffset = 0x14; // pvArbitrary, reserved for application use
+    } else if (ST->isTargetFreeBSD()) {
+      report_fatal_error("Segmented stacks not supported on FreeBSD i386.");
     } else {
       report_fatal_error("Segmented stacks not supported on this platform.");
     }
diff --git a/test/CodeGen/X86/segmented-stacks.ll b/test/CodeGen/X86/segmented-stacks.ll
index 4c4c542785..3650304a08 100644
--- a/test/CodeGen/X86/segmented-stacks.ll
+++ b/test/CodeGen/X86/segmented-stacks.ll
@@ -3,6 +3,7 @@
 ; RUN: llc < %s -mtriple=i686-darwin -segmented-stacks -verify-machineinstrs | FileCheck %s -check-prefix=X32-Darwin
 ; RUN: llc < %s -mtriple=x86_64-darwin -segmented-stacks -verify-machineinstrs | FileCheck %s -check-prefix=X64-Darwin
 ; RUN: llc < %s -mtriple=i686-mingw32 -segmented-stacks -verify-machineinstrs | FileCheck %s -check-prefix=X32-MinGW
+; RUN: llc < %s -mtriple=x86_64-freebsd -segmented-stacks -verify-machineinstrs | FileCheck %s -check-prefix=X64-FreeBSD
 
 ; We used to crash with filetype=obj
 ; RUN: llc < %s -mtriple=i686-linux -segmented-stacks -filetype=obj
@@ -10,6 +11,7 @@
 ; RUN: llc < %s -mtriple=i686-darwin -segmented-stacks -filetype=obj
 ; RUN: llc < %s -mtriple=x86_64-darwin -segmented-stacks -filetype=obj
 ; RUN: llc < %s -mtriple=i686-mingw32 -segmented-stacks -filetype=obj
+; RUN: llc < %s -mtriple=x86_64-freebsd -segmented-stacks -filetype=obj
 
 ; Just to prevent the alloca from being optimized away
 declare void @dummy_use(i32*, i32)
@@ -70,6 +72,16 @@ define void @test_basic() {
 ; X32-MinGW-NEXT:  calll ___morestack
 ; X32-MinGW-NEXT:  ret
 
+; X64-FreeBSD:       test_basic:
+
+; X64-FreeBSD:       cmpq %fs:24, %rsp
+; X64-FreeBSD-NEXT:  ja      .LBB0_2
+
+; X64-FreeBSD:       movabsq $40, %r10
+; X64-FreeBSD-NEXT:  movabsq $0, %r11
+; X64-FreeBSD-NEXT:  callq __morestack
+; X64-FreeBSD-NEXT:  ret
+
 }
 
 define i32 @test_nested(i32 * nest %closure, i32 %other) {
@@ -122,6 +134,16 @@ define i32 @test_nested(i32 * nest %closure, i32 %other) {
 ; X32-MinGW-NEXT:  calll ___morestack
 ; X32-MinGW-NEXT:  ret
 
+; X64-FreeBSD:       cmpq %fs:24, %rsp
+; X64-FreeBSD-NEXT:  ja      .LBB1_2
+
+; X64-FreeBSD:       movq %r10, %rax
+; X64-FreeBSD-NEXT:  movabsq $0, %r10
+; X64-FreeBSD-NEXT:  movabsq $0, %r11
+; X64-FreeBSD-NEXT:  callq __morestack
+; X64-FreeBSD-NEXT:  ret
+; X64-FreeBSD-NEXT:  movq %rax, %r10
+
 }
 
 define void @test_large() {
@@ -175,6 +197,15 @@ define void @test_large() {
 ; X32-MinGW-NEXT:  calll ___morestack
 ; X32-MinGW-NEXT:  ret
 
+; X64-FreeBSD:       leaq -40008(%rsp), %r11
+; X64-FreeBSD-NEXT:  cmpq %fs:24, %r11
+; X64-FreeBSD-NEXT:  ja      .LBB2_2
+
+; X64-FreeBSD:       movabsq $40008, %r10
+; X64-FreeBSD-NEXT:  movabsq $0, %r11
+; X64-FreeBSD-NEXT:  callq __morestack
+; X64-FreeBSD-NEXT:  ret
+
 }
 
 define fastcc void @test_fastcc() {
@@ -233,6 +264,16 @@ define fastcc void @test_fastcc() {
 ; X32-MinGW-NEXT:  calll ___morestack
 ; X32-MinGW-NEXT:  ret
 
+; X64-FreeBSD:       test_fastcc:
+
+; X64-FreeBSD:       cmpq %fs:24, %rsp
+; X64-FreeBSD-NEXT:  ja      .LBB3_2
+
+; X64-FreeBSD:       movabsq $40, %r10
+; X64-FreeBSD-NEXT:  movabsq $0, %r11
+; X64-FreeBSD-NEXT:  callq __morestack
+; X64-FreeBSD-NEXT:  ret
+
 }
 
 define fastcc void @test_fastcc_large() {
@@ -296,6 +337,17 @@ define fastcc void @test_fastcc_large() {
 ; X32-MinGW-NEXT:  calll ___morestack
 ; X32-MinGW-NEXT:  ret
 
+; X64-FreeBSD:       test_fastcc_large:
+
+; X64-FreeBSD:       leaq -40008(%rsp), %r11
+; X64-FreeBSD-NEXT:  cmpq %fs:24, %r11
+; X64-FreeBSD-NEXT:  ja      .LBB4_2
+
+; X64-FreeBSD:       movabsq $40008, %r10
+; X64-FreeBSD-NEXT:  movabsq $0, %r11
+; X64-FreeBSD-NEXT:  callq __morestack
+; X64-FreeBSD-NEXT:  ret
+
 }
 
 define fastcc void @test_fastcc_large_with_ecx_arg(i32 %a) {