From: Reid Kleckner <rnk@google.com>
Date: Wed, 7 Oct 2015 17:49:32 +0000 (+0000)
Subject: [WinEH] Fix two minor issues in __CxxFrameHandler3 tables
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5e3eac7a27c0ee53b908d554395eeff7fb5097c3;p=oota-llvm.git

[WinEH] Fix two minor issues in __CxxFrameHandler3 tables

There was an off-by-one bug in ip2state tables which manifested when one
call immediately preceded the try-range of the next. The return address
of the previous call would appear to be within the try range of the next
scope, resulting in extra destructors or catches running.

We also computed the wrong offset for catch parameter stack objects. The
offset should be from RSP, not from RBP.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249578 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/Target/TargetFrameLowering.h b/include/llvm/Target/TargetFrameLowering.h
index 2e8c178914e..9585f7c3498 100644
--- a/include/llvm/Target/TargetFrameLowering.h
+++ b/include/llvm/Target/TargetFrameLowering.h
@@ -236,10 +236,11 @@ public:
                                      unsigned &FrameReg) const;
 
   /// Same as above, except that the 'base register' will always be RSP, not
-  /// RBP on x86.  This is used exclusively for lowering STATEPOINT nodes.
+  /// RBP on x86. This is generally used for emitting statepoint or EH tables
+  /// that use offsets from RSP.
   /// TODO: This should really be a parameterizable choice.
   virtual int getFrameIndexReferenceFromSP(const MachineFunction &MF, int FI,
-                                          unsigned &FrameReg) const {
+                                           unsigned &FrameReg) const {
     // default to calling normal version, we override this on x86 only
     llvm_unreachable("unimplemented for non-x86");
     return 0;
diff --git a/lib/CodeGen/AsmPrinter/WinException.cpp b/lib/CodeGen/AsmPrinter/WinException.cpp
index 4f1d5cb864a..bc2c9ee635c 100644
--- a/lib/CodeGen/AsmPrinter/WinException.cpp
+++ b/lib/CodeGen/AsmPrinter/WinException.cpp
@@ -791,7 +791,7 @@ void WinException::computeIP2StateTable(
       // Emit an entry indicating that PCs after 'Label' have this EH state.
       if (I.State != LastEHState)
         IPToStateTable.push_back(
-            std::make_pair(create32bitRef(I.BeginLabel), I.State));
+            std::make_pair(getLabelPlusOne(I.BeginLabel), I.State));
       LastEHState = I.State;
       LastEndLabel = I.EndLabel;
     }
diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index 63825b5dde9..495da5c07d1 100644
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -820,12 +820,11 @@ void PEI::replaceFrameIndices(MachineFunction &Fn) {
           Fn, FuncInfo.UnwindHelpFrameIdx, FrameReg);
     for (WinEHTryBlockMapEntry &TBME : FuncInfo.TryBlockMap) {
       for (WinEHHandlerType &H : TBME.HandlerArray) {
-        unsigned UnusedReg;
         if (H.CatchObj.FrameIndex == INT_MAX)
           H.CatchObj.FrameOffset = INT_MAX;
         else
-          H.CatchObj.FrameOffset =
-              TFI.getFrameIndexReference(Fn, H.CatchObj.FrameIndex, UnusedReg);
+          H.CatchObj.FrameOffset = TFI.getFrameIndexReferenceFromSP(
+              Fn, H.CatchObj.FrameIndex, FrameReg);
       }
     }
   }
diff --git a/test/CodeGen/X86/win-catchpad.ll b/test/CodeGen/X86/win-catchpad.ll
index 45d1085f3ad..67875f23060 100644
--- a/test/CodeGen/X86/win-catchpad.ll
+++ b/test/CodeGen/X86/win-catchpad.ll
@@ -120,7 +120,7 @@ catchendblock:                                    ; preds = %catch, %catch.2, %c
 ; X86: $handlerMap$0$try_catch_catch:
 ; X86-NEXT:   .long   0
 ; X86-NEXT:   .long   "??_R0H@8"
-; X86-NEXT:   .long   -20
+; X86-NEXT:   .long   24
 ; X86-NEXT:   .long   "?catch$[[catch1bb]]@?0?try_catch_catch@4HA"
 ; X86-NEXT:   .long   64
 ; X86-NEXT:   .long   0
@@ -156,7 +156,7 @@ catchendblock:                                    ; preds = %catch, %catch.2, %c
 ; X64: .seh_endprologue
 ; X64-DAG: .Ltmp4
 ; X64-DAG: leaq -[[local_offs]](%rbp), %rdx
-; X64-DAG: movl [[e_addr:[-0-9]+]](%rbp), %ecx
+; X64-DAG: movl -4(%rbp), %ecx
 ; X64: callq f
 ; X64: leaq [[contbb]](%rip), %rax
 ; X64-NEXT: addq $32, %rsp
@@ -204,7 +204,7 @@ catchendblock:                                    ; preds = %catch, %catch.2, %c
 ; X64-NEXT:   .long   0
 ; X64-NEXT:   .long   "??_R0H@8"@IMGREL
 ; FIXME: This should probably be offset from rsp, not rbp.
-; X64-NEXT:   .long   [[e_addr]]
+; X64-NEXT:   .long   44
 ; X64-NEXT:   .long   "?catch$[[catch1bb]]@?0?try_catch_catch@4HA"@IMGREL
 ; X64-NEXT:   .long   56
 ; X64-NEXT:   .long   64
@@ -216,9 +216,9 @@ catchendblock:                                    ; preds = %catch, %catch.2, %c
 ; X64: $ip2state$try_catch_catch:
 ; X64-NEXT: .long   .Lfunc_begin0@IMGREL
 ; X64-NEXT: .long   -1
-; X64-NEXT: .long   .Ltmp0@IMGREL
+; X64-NEXT: .long   .Ltmp0@IMGREL+1
 ; X64-NEXT: .long   0
-; X64-NEXT: .long   .Ltmp4@IMGREL
+; X64-NEXT: .long   .Ltmp4@IMGREL+1
 ; X64-NEXT: .long   1
 ; X64-NEXT: .long   .Ltmp3@IMGREL+1
 ; X64-NEXT: .long   -1
@@ -353,7 +353,7 @@ catchendblock:
 ; X64-LABEL: $ip2state$branch_to_normal_dest:
 ; X64-NEXT: .long   .Lfunc_begin1@IMGREL
 ; X64-NEXT: .long   -1
-; X64-NEXT: .long   .Ltmp[[before_call]]@IMGREL
+; X64-NEXT: .long   .Ltmp[[before_call]]@IMGREL+1
 ; X64-NEXT: .long   0
 ; X64-NEXT: .long   .Ltmp[[after_call]]@IMGREL+1
 ; X64-NEXT: .long   -1