From 650d9427f075becaa35a675af8169f60eeb8e756 Mon Sep 17 00:00:00 2001
From: Matthias Braun <matze@braunis.de>
Date: Thu, 16 Jul 2015 22:34:20 +0000
Subject: [PATCH] Arm: Don't define a label twice with two setjmps in a
 function.

Constructing a name based on the function name didn't give us a unique
symbol if we had more than one setjmp in a function. Using
MCContext::createTempSymbol() always gives us a unique name.

Differential Revision: http://reviews.llvm.org/D9314

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242482 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMAsmPrinter.cpp      | 15 +----
 lib/Target/ARM/ARMAsmPrinter.h        |  2 -
 test/CodeGen/Thumb2/setjmp_longjmp.ll | 89 +++++++++++++++++++++++++++
 3 files changed, 92 insertions(+), 14 deletions(-)
 create mode 100644 test/CodeGen/Thumb2/setjmp_longjmp.ll

diff --git a/lib/Target/ARM/ARMAsmPrinter.cpp b/lib/Target/ARM/ARMAsmPrinter.cpp
index e490af50b34..7f982eeabb9 100644
--- a/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -205,15 +205,6 @@ GetARMJTIPICJumpTableLabel(unsigned uid) const {
   return OutContext.getOrCreateSymbol(Name);
 }
 
-
-MCSymbol *ARMAsmPrinter::GetARMSJLJEHLabel() const {
-  const DataLayout &DL = getDataLayout();
-  SmallString<60> Name;
-  raw_svector_ostream(Name) << DL.getPrivateGlobalPrefix() << "SJLJEH"
-                            << getFunctionNumber();
-  return OutContext.getOrCreateSymbol(Name);
-}
-
 bool ARMAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
                                     unsigned AsmVariant, const char *ExtraCode,
                                     raw_ostream &O) {
@@ -1649,12 +1640,12 @@ void ARMAsmPrinter::EmitInstruction(const MachineInstr *MI) {
     // adds $val, #7
     // str $val, [$src, #4]
     // movs r0, #0
-    // b 1f
+    // b LSJLJEH
     // movs r0, #1
-    // 1:
+    // LSJLJEH:
     unsigned SrcReg = MI->getOperand(0).getReg();
     unsigned ValReg = MI->getOperand(1).getReg();
-    MCSymbol *Label = GetARMSJLJEHLabel();
+    MCSymbol *Label = OutContext.createTempSymbol("SJLJEH", false, true);
     OutStreamer->AddComment("eh_setjmp begin");
     EmitToStreamer(*OutStreamer, MCInstBuilder(ARM::tMOVr)
       .addReg(ValReg)
diff --git a/lib/Target/ARM/ARMAsmPrinter.h b/lib/Target/ARM/ARMAsmPrinter.h
index 53b29204d57..fb925f162f7 100644
--- a/lib/Target/ARM/ARMAsmPrinter.h
+++ b/lib/Target/ARM/ARMAsmPrinter.h
@@ -119,8 +119,6 @@ private:
   MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol);
   MCSymbol *GetARMJTIPICJumpTableLabel(unsigned uid) const;
 
-  MCSymbol *GetARMSJLJEHLabel() const;
-
   MCSymbol *GetARMGVSymbol(const GlobalValue *GV, unsigned char TargetFlags);
 
 public:
diff --git a/test/CodeGen/Thumb2/setjmp_longjmp.ll b/test/CodeGen/Thumb2/setjmp_longjmp.ll
new file mode 100644
index 00000000000..9e0fad00c14
--- /dev/null
+++ b/test/CodeGen/Thumb2/setjmp_longjmp.ll
@@ -0,0 +1,89 @@
+; RUN: llc %s -o - | FileCheck %s
+target triple = "thumbv7-apple-ios"
+
+declare i32 @llvm.eh.sjlj.setjmp(i8*)
+declare void @llvm.eh.sjlj.longjmp(i8*)
+declare i8* @llvm.frameaddress(i32)
+declare i8* @llvm.stacksave()
+@g = external global i32
+
+; CHECK-LABEL: double_foobar
+;
+; setjmp sequence:
+; CHECK: mov [[PCREG:r[0-9]+]], pc
+; CHECK-NEXT: adds [[PCREG]], [[PCREG]], #7
+; CHECK-NEXT: str [[PCREG]], {{\[}}[[BUFREG:r[0-9]+]], #4]
+; CHECK-NEXT: movs r0, #0
+; CHECK-NEXT: b [[LABEL:L[a-zA-Z0-9]+]]
+; CHECK-NEXT: movs r0, #1
+; CHECK-NEXT: [[LABEL]]:
+;
+; setjmp sequence 2:
+; CHECK: mov [[PCREG:r[0-9]+]], pc
+; CHECK-NEXT: adds [[PCREG]], [[PCREG]], #7
+; CHECK-NEXT: str [[PCREG]], {{\[}}[[BUFREG:r[0-9]+]], #4]
+; CHECK-NEXT: movs r0, #0
+; CHECK-NEXT: b [[LABEL:L[a-zA-Z0-9]+]]
+; CHECK-NEXT: movs r0, #1
+; CHECK-NEXT: [[LABEL]]:
+
+; longjmp sequence:
+; CHECK: ldr [[TEMPREG:r[0-9]+]], [{{\s*}}[[BUFREG:r[0-9]+]], #8]
+; CHECK-NEXT: mov sp, [[TEMPREG]]
+; CHECK-NEXT: ldr [[DESTREG:r[0-9]+]], {{\[}}[[BUFREG]], #4]
+; CHECK-NEXT: ldr r7, {{\[}}[[BUFREG]]{{\]}}
+; CHECK-NEXT: bx [[DESTREG]]
+;
+; longjmp sequence2:
+; CHECK: ldr [[TEMPREG:r[0-9]+]], [{{\s*}}[[BUFREG:r[0-9]+]], #8]
+; CHECK-NEXT: mov sp, [[TEMPREG]]
+; CHECK-NEXT: ldr [[DESTREG:r[0-9]+]], {{\[}}[[BUFREG]], #4]
+; CHECK-NEXT: ldr r7, {{\[}}[[BUFREG]]{{\]}}
+; CHECK-NEXT: bx [[DESTREG]]
+define void @double_foobar() {
+entry:
+  %buf = alloca [5 x i8*], align 4
+  %bufptr = bitcast [5 x i8*]* %buf to i8*
+  %arraydecay = getelementptr inbounds [5 x i8*], [5 x i8*]* %buf, i32 0, i32 0
+
+  %fa = tail call i8* @llvm.frameaddress(i32 0)
+  store i8* %fa, i8** %arraydecay, align 4
+  %ss = tail call i8* @llvm.stacksave()
+  %ssgep = getelementptr [5 x i8*], [5 x i8*]* %buf, i32 0, i32 2
+  store i8* %ss, i8** %ssgep, align 4
+
+  %setjmpres = call i32 @llvm.eh.sjlj.setjmp(i8* %bufptr)
+  %tobool = icmp ne i32 %setjmpres, 0
+  br i1 %tobool, label %if.then, label %if.else
+
+if.then:
+  store volatile i32 1, i32* @g, align 4
+  br label %if.end
+
+if.else:
+  store volatile i32 0, i32* @g, align 4
+  call void @llvm.eh.sjlj.longjmp(i8* %bufptr)
+  unreachable
+
+if.end:
+  %fa2 = tail call i8* @llvm.frameaddress(i32 0)
+  store i8* %fa2, i8** %arraydecay, align 4
+  %ss2 = tail call i8* @llvm.stacksave()
+  store i8* %ss2, i8** %ssgep, align 4
+
+  %setjmpres2 = call i32 @llvm.eh.sjlj.setjmp(i8* %bufptr)
+  %tobool2 = icmp ne i32 %setjmpres2, 0
+  br i1 %tobool2, label %if2.then, label %if2.else
+
+if2.then:
+  store volatile i32 3, i32* @g, align 4
+  br label %if2.end
+
+if2.else:
+  store volatile i32 2, i32* @g, align 4
+  call void @llvm.eh.sjlj.longjmp(i8* %bufptr)
+  unreachable
+
+if2.end:
+  ret void
+}
-- 
2.34.1