[llvm] 78a5706 - [CodeGen] Restore accessing __stack_chk_guard via a .refptr stub on mingw after 2518433f861fcb87

[Martin Storsjö via llvm-commits]

Author: Martin Storsjö
Date: 2020-12-07T09:35:12+02:00
New Revision: 78a57069b53a08d5aef98a8472fcfa73dbbc8771

URL: https://github.com/llvm/llvm-project/commit/78a57069b53a08d5aef98a8472fcfa73dbbc8771
DIFF: https://github.com/llvm/llvm-project/commit/78a57069b53a08d5aef98a8472fcfa73dbbc8771.diff

LOG: [CodeGen] Restore accessing __stack_chk_guard via a .refptr stub on mingw after 2518433f861fcb87

Add tests for this particular detail for x86 and arm (similar tests
already existed for x86_64 and aarch64).

The libssp implementation may be located in a separate DLL, and in
those cases, the references need to be in a .refptr stub, to avoid
needing to touch up code in the text section at runtime (which is
supported but inefficient for x86, and unsupported for arm).

Differential Revision: https://reviews.llvm.org/D92738

Added: 
    llvm/test/CodeGen/ARM/win32-ssp.ll

Modified: 
    llvm/lib/CodeGen/TargetLoweringBase.cpp
    llvm/test/CodeGen/X86/win32-ssp.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
index 61a2de711af8..7dfd76ce5de0 100644
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -1973,7 +1973,8 @@ void TargetLoweringBase::insertSSPDeclarations(Module &M) const {
     auto *GV = new GlobalVariable(M, Type::getInt8PtrTy(M.getContext()), false,
                                   GlobalVariable::ExternalLinkage, nullptr,
                                   "__stack_chk_guard");
-    if (getTargetMachine().getRelocationModel() == Reloc::Static)
+    if (TM.getRelocationModel() == Reloc::Static &&
+        !TM.getTargetTriple().isWindowsGNUEnvironment())
       GV->setDSOLocal(true);
   }
 }

diff  --git a/llvm/test/CodeGen/ARM/win32-ssp.ll b/llvm/test/CodeGen/ARM/win32-ssp.ll
new file mode 100644
index 000000000000..292ef9f65df1
--- /dev/null
+++ b/llvm/test/CodeGen/ARM/win32-ssp.ll
@@ -0,0 +1,23 @@
+; RUN: llc -mtriple=thumbv7-w64-mingw32 < %s -o - | FileCheck --check-prefix=MINGW %s
+
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
+declare dso_local void @other(i8*)
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
+
+define dso_local void @func() sspstrong {
+entry:
+; MINGW-LABEL: func:
+; MINGW: movw [[REG:r[0-9]+]], :lower16:.refptr.__stack_chk_guard
+; MINGW: movt [[REG]], :upper16:.refptr.__stack_chk_guard
+; MINGW: ldr [[REG2:r[0-9]+]], {{\[}}[[REG]]]
+; MINGW: ldr {{r[0-9]+}}, {{\[}}[[REG2]]]
+; MINGW: bl other
+; MINGW: ldr {{r[0-9]+}}, {{\[}}[[REG2]]]
+; MINGW: bl __stack_chk_fail
+
+  %c = alloca i8, align 1
+  call void @llvm.lifetime.start.p0i8(i64 1, i8* nonnull %c)
+  call void @other(i8* nonnull %c)
+  call void @llvm.lifetime.end.p0i8(i64 1, i8* nonnull %c)
+  ret void
+}

diff  --git a/llvm/test/CodeGen/X86/win32-ssp.ll b/llvm/test/CodeGen/X86/win32-ssp.ll
index b3e6333000ad..0626bd98a3e3 100644
--- a/llvm/test/CodeGen/X86/win32-ssp.ll
+++ b/llvm/test/CodeGen/X86/win32-ssp.ll
@@ -1,6 +1,7 @@
 ; RUN: llc -mtriple=x86_64-w64-mingw32        < %s -o - | FileCheck --check-prefix=MINGW %s
 ; RUN: llc -mtriple=x86_64-pc-windows-itanium < %s -o - | FileCheck --check-prefix=MSVC  %s
 ; RUN: llc -mtriple=x86_64-pc-windows-msvc    < %s -o - | FileCheck --check-prefix=MSVC  %s
+; RUN: llc -mtriple=i686-w64-mingw32          < %s -o - | FileCheck --check-prefix=MINGW %s
 
 declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
 declare dso_local void @other(i8*)
@@ -9,12 +10,11 @@ declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
 define dso_local void @func() sspstrong {
 entry:
 ; MINGW-LABEL: func:
-; MINGW: mov{{l|q}}  .refptr.__stack_chk_guard(%rip), [[REG:%[a-z]+]]
+; MINGW: mov{{l|q}}  .refptr.[[PREFIX:_?]]__stack_chk_guard{{(\(%rip\))?}}, [[REG:%[a-z]+]]
 ; MINGW: mov{{l|q}}  ([[REG]])
-; MINGW: callq other
+; MINGW: call{{l|q}} [[PREFIX]]other
 ; MINGW: mov{{l|q}}  ([[REG]])
-; MINGW: callq __stack_chk_fail
-; MINGW: .seh_endproc
+; MINGW: call{{l|q}} [[PREFIX]]__stack_chk_fail
 
 ; MSVC-LABEL: func:
 ; MSVC: mov{{l|q}} __security_cookie