Add segmented stack support for DragonFlyBSD

[mneumann]

Summary

This patch adds support for segmented stacks for DragonFlyBSD. It is required to port the Rust programming language to DragonFly. With this patch rustc can generate code targeted at DragonFly.

[mneumann]

Ping!

Am 29.07.2014 um 15:20 schrieb Michael Neumann:

This patch adds support for segmented stacks for DragonFlyBSD. It is required to port the Rust programming language to DragonFly. With this patch rustc can generate code targeted at DragonFly.

http://reviews.llvm.org/D4705

Files:

lib/Target/X86/X86FrameLowering.cpp
lib/Target/X86/X86Subtarget.h

Index: lib/Target/X86/X86FrameLowering.cpp

• lib/Target/X86/X86FrameLowering.cpp

+++ lib/Target/X86/X86FrameLowering.cpp
@@ -1328,7 +1328,8 @@

if (MF.getFunction()->isVarArg())
  report_fatal_error("Segmented stacks do not support vararg functions.");
if (!STI.isTargetLinux() && !STI.isTargetDarwin() &&

• !STI.isTargetWin32() && !STI.isTargetWin64() && !STI.isTargetFreeBSD())

+ !STI.isTargetWin32() && !STI.isTargetWin64() &&
+ !STI.isTargetFreeBSD() && !STI.isTargetDragonFly())

  report_fatal_error("Segmented stacks not supported on this platform.");

// Eventually StackSize will be calculated by a link-time pass; which will

@@ -1382,6 +1383,9 @@

} else if (STI.isTargetFreeBSD()) {
  TlsReg = X86::FS;
  TlsOffset = 0x18;

+ } else if (STI.isTargetDragonFly()) {
+ TlsReg = X86::FS;
+ TlsOffset = 0x20; // use tls_tcb.tcb_segstack

} else {
  report_fatal_error("Segmented stacks not supported on this platform.");
}

@@ -1404,6 +1408,9 @@

} else if (STI.isTargetWin32()) {
  TlsReg = X86::FS;
  TlsOffset = 0x14; // pvArbitrary, reserved for application use

+ } else if (STI.isTargetDragonFly()) {
+ TlsReg = X86::FS;
+ TlsOffset = 0x10; // use tls_tcb.tcb_segstack

} else if (STI.isTargetFreeBSD()) {
  report_fatal_error("Segmented stacks not supported on FreeBSD i386.");
} else {

Index: lib/Target/X86/X86Subtarget.h

• lib/Target/X86/X86Subtarget.h

+++ lib/Target/X86/X86Subtarget.h
@@ -371,6 +371,9 @@

bool isTargetFreeBSD() const {
  return TargetTriple.getOS() == Triple::FreeBSD;
}

+ bool isTargetDragonFly() const {
+ return TargetTriple.getOS() == Triple::DragonFly;
+ }

bool isTargetSolaris() const {
  return TargetTriple.getOS() == Triple::Solaris;
}

[• rafael]

You should add a testcase showing what code llc produces for both 32 and 64 bits.

[mneumann]

Add codegen test cases and fix a bug in the X32 generation.

[• rafael]

LGTM with it clang-formated.

include/llvm/ADT/Triple.h

380

This fits in one line, no? Can you git-clang-format the patch?

[mneumann]

clang-formatted version

[• rafael]

r224936

include/llvm/ADT/Triple.h

     return getOS() == Triple::FreeBSD;
   }
 
+  bool isOSDragonFly() const { return getOS() == Triple::DragonFly; }
+
   bool isOSSolaris() const {
     return getOS() == Triple::Solaris;
   }

lib/Target/X86/X86FrameLowering.cpp

 
   if (MF.getFunction()->isVarArg())
     report_fatal_error("Segmented stacks do not support vararg functions.");
-  if (!STI.isTargetLinux() && !STI.isTargetDarwin() &&
-      !STI.isTargetWin32() && !STI.isTargetWin64() && !STI.isTargetFreeBSD())
+  if (!STI.isTargetLinux() && !STI.isTargetDarwin() && !STI.isTargetWin32() &&
+      !STI.isTargetWin64() && !STI.isTargetFreeBSD() &&
+      !STI.isTargetDragonFly())
     report_fatal_error("Segmented stacks not supported on this platform.");
 
   // Eventually StackSize will be calculated by a link-time pass; which will

     } else if (STI.isTargetFreeBSD()) {
       TlsReg = X86::FS;
       TlsOffset = 0x18;
+    } else if (STI.isTargetDragonFly()) {
+      TlsReg = X86::FS;
+      TlsOffset = 0x20; // use tls_tcb.tcb_segstack
     } else {
       report_fatal_error("Segmented stacks not supported on this platform.");
     }

     } else if (STI.isTargetWin32()) {
       TlsReg = X86::FS;
       TlsOffset = 0x14; // pvArbitrary, reserved for application use
+    } else if (STI.isTargetDragonFly()) {
+      TlsReg = X86::FS;
+      TlsOffset = 0x10; // use tls_tcb.tcb_segstack
     } else if (STI.isTargetFreeBSD()) {
       report_fatal_error("Segmented stacks not supported on FreeBSD i386.");
     } else {

       BuildMI(checkMBB, DL, TII.get(X86::LEA32r), ScratchReg).addReg(X86::ESP)
         .addImm(1).addReg(0).addImm(-StackSize).addReg(0);
 
-    if (STI.isTargetLinux() || STI.isTargetWin32() || STI.isTargetWin64()) {
+    if (STI.isTargetLinux() || STI.isTargetWin32() || STI.isTargetWin64() ||
+        STI.isTargetDragonFly()) {
       BuildMI(checkMBB, DL, TII.get(X86::CMP32rm)).addReg(ScratchReg)
         .addReg(0).addImm(0).addReg(0).addImm(TlsOffset).addReg(TlsReg);
     } else if (STI.isTargetDarwin()) {

lib/Target/X86/X86Subtarget.h

 
   bool isTargetDarwin() const { return TargetTriple.isOSDarwin(); }
   bool isTargetFreeBSD() const { return TargetTriple.isOSFreeBSD(); }
+  bool isTargetDragonFly() const { return TargetTriple.isOSDragonFly(); }
   bool isTargetSolaris() const { return TargetTriple.isOSSolaris(); }
 
   bool isTargetELF() const { return TargetTriple.isOSBinFormatELF(); }

test/CodeGen/X86/segmented-stacks.ll

 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-darwin -verify-machineinstrs | FileCheck %s -check-prefix=X64-Darwin
 ; RUN: llc < %s -mcpu=generic -mtriple=i686-mingw32 -verify-machineinstrs | FileCheck %s -check-prefix=X32-MinGW
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-freebsd -verify-machineinstrs | FileCheck %s -check-prefix=X64-FreeBSD
+; RUN: llc < %s -mcpu=generic -mtriple=i686-dragonfly -verify-machineinstrs | FileCheck %s -check-prefix=X32-DFlyBSD
+; RUN: llc < %s -mcpu=generic -mtriple=x86_64-dragonfly -verify-machineinstrs | FileCheck %s -check-prefix=X64-DFlyBSD
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-mingw32 -verify-machineinstrs | FileCheck %s -check-prefix=X64-MinGW
 
 ; We used to crash with filetype=obj

 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-darwin -filetype=obj
 ; RUN: llc < %s -mcpu=generic -mtriple=i686-mingw32 -filetype=obj
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-freebsd -filetype=obj
+; RUN: llc < %s -mcpu=generic -mtriple=i686-dragonfly -filetype=obj
+; RUN: llc < %s -mcpu=generic -mtriple=x86_64-dragonfly -filetype=obj
 ; RUN: llc < %s -mcpu=generic -mtriple=x86_64-mingw32 -filetype=obj
 
 ; RUN: not llc < %s -mcpu=generic -mtriple=x86_64-solaris 2> %t.log

 ; X64-FreeBSD-NEXT:  callq __morestack
 ; X64-FreeBSD-NEXT:  ret
 
+; X32-DFlyBSD-LABEL:       test_basic:
+
+; X32-DFlyBSD:       cmpl %fs:16, %esp
+; X32-DFlyBSD-NEXT:  ja      .LBB0_2
+
+; X32-DFlyBSD:       pushl $0
+; X32-DFlyBSD-NEXT:  pushl $48
+; X32-DFlyBSD-NEXT:  calll __morestack
+; X32-DFlyBSD-NEXT:  ret
+
+; X64-DFlyBSD-LABEL:       test_basic:
+
+; X64-DFlyBSD:       cmpq %fs:32, %rsp
+; X64-DFlyBSD-NEXT:  ja      .LBB0_2
+
+; X64-DFlyBSD:       movabsq $40, %r10
+; X64-DFlyBSD-NEXT:  movabsq $0, %r11
+; X64-DFlyBSD-NEXT:  callq __morestack
+; X64-DFlyBSD-NEXT:  ret
+
 }
 
 define i32 @test_nested(i32 * nest %closure, i32 %other) #0 {

 ; X64-FreeBSD-NEXT:  ret
 ; X64-FreeBSD-NEXT:  movq %rax, %r10
 
+; X32-DFlyBSD:       cmpl %fs:16, %esp
+; X32-DFlyBSD-NEXT:  ja      .LBB1_2
+
+; X32-DFlyBSD:       pushl $4
+; X32-DFlyBSD-NEXT:  pushl $52
+; X32-DFlyBSD-NEXT:  calll __morestack
+; X32-DFlyBSD-NEXT:  ret
+
+; X64-DFlyBSD:       cmpq %fs:32, %rsp
+; X64-DFlyBSD-NEXT:  ja      .LBB1_2
+
+; X64-DFlyBSD:       movq %r10, %rax
+; X64-DFlyBSD-NEXT:  movabsq $56, %r10
+; X64-DFlyBSD-NEXT:  movabsq $0, %r11
+; X64-DFlyBSD-NEXT:  callq __morestack
+; X64-DFlyBSD-NEXT:  ret
+; X64-DFlyBSD-NEXT:  movq %rax, %r10
+
 }
 
 define void @test_large() #0 {

 ; X64-FreeBSD-NEXT:  callq __morestack
 ; X64-FreeBSD-NEXT:  ret
 
+; X32-DFlyBSD:       leal -40008(%esp), %ecx
+; X32-DFlyBSD-NEXT:  cmpl %fs:16, %ecx
+; X32-DFlyBSD-NEXT:  ja      .LBB2_2
+
+; X32-DFlyBSD:       pushl $0
+; X32-DFlyBSD-NEXT:  pushl $40008
+; X32-DFlyBSD-NEXT:  calll __morestack
+; X32-DFlyBSD-NEXT:  ret
+
+; X64-DFlyBSD:       leaq -40008(%rsp), %r11
+; X64-DFlyBSD-NEXT:  cmpq %fs:32, %r11
+; X64-DFlyBSD-NEXT:  ja      .LBB2_2
+
+; X64-DFlyBSD:       movabsq $40008, %r10
+; X64-DFlyBSD-NEXT:  movabsq $0, %r11
+; X64-DFlyBSD-NEXT:  callq __morestack
+; X64-DFlyBSD-NEXT:  ret
+
 }
 
 define fastcc void @test_fastcc() #0 {

 ; X64-FreeBSD-NEXT:  callq __morestack
 ; X64-FreeBSD-NEXT:  ret
 
+; X32-DFlyBSD-LABEL:       test_fastcc:
+
+; X32-DFlyBSD:       cmpl %fs:16, %esp
+; X32-DFlyBSD-NEXT:  ja      .LBB3_2
+
+; X32-DFlyBSD:       pushl $0
+; X32-DFlyBSD-NEXT:  pushl $48
+; X32-DFlyBSD-NEXT:  calll __morestack
+; X32-DFlyBSD-NEXT:  ret
+
+; X64-DFlyBSD-LABEL:       test_fastcc:
+
+; X64-DFlyBSD:       cmpq %fs:32, %rsp
+; X64-DFlyBSD-NEXT:  ja      .LBB3_2
+
+; X64-DFlyBSD:       movabsq $40, %r10
+; X64-DFlyBSD-NEXT:  movabsq $0, %r11
+; X64-DFlyBSD-NEXT:  callq __morestack
+; X64-DFlyBSD-NEXT:  ret
+
 }
 
 define fastcc void @test_fastcc_large() #0 {

 ; X64-FreeBSD-NEXT:  callq __morestack
 ; X64-FreeBSD-NEXT:  ret
 
+; X32-DFlyBSD-LABEL:       test_fastcc_large:
+
+; X32-DFlyBSD:       leal -40008(%esp), %eax
+; X32-DFlyBSD-NEXT:  cmpl %fs:16, %eax
+; X32-DFlyBSD-NEXT:  ja      .LBB4_2
+
+; X32-DFlyBSD:       pushl $0
+; X32-DFlyBSD-NEXT:  pushl $40008
+; X32-DFlyBSD-NEXT:  calll __morestack
+; X32-DFlyBSD-NEXT:  ret
+
+; X64-DFlyBSD-LABEL:       test_fastcc_large:
+
+; X64-DFlyBSD:       leaq -40008(%rsp), %r11
+; X64-DFlyBSD-NEXT:  cmpq %fs:32, %r11
+; X64-DFlyBSD-NEXT:  ja      .LBB4_2
+
+; X64-DFlyBSD:       movabsq $40008, %r10
+; X64-DFlyBSD-NEXT:  movabsq $0, %r11
+; X64-DFlyBSD-NEXT:  callq __morestack
+; X64-DFlyBSD-NEXT:  ret
+
 }
 
 define fastcc void @test_fastcc_large_with_ecx_arg(i32 %a) #0 {

 
 ; X64-FreeBSD-LABEL: test_nostack:
 ; X64-FreeBSD-NOT:   callq __morestack
+
+; X32-DFlyBSD-LABEL: test_nostack:
+; X32-DFlyBSD-NOT:   calll __morestack
+
+; X64-DFlyBSD-LABEL: test_nostack:
+; X64-DFlyBSD-NOT:   callq __morestack
 }
 
 attributes #0 = { "split-stack" }