<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Oct 13, 2017, at 4:08 PM, Peter Collingbourne <<a href="mailto:peter@pcc.me.uk" class="">peter@pcc.me.uk</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class="gmail_extra"><div class="gmail_quote">On Fri, Oct 13, 2017 at 4:06 PM, Peter Collingbourne <span dir="ltr" class=""><<a href="mailto:peter@pcc.me.uk" target="_blank" class="">peter@pcc.me.uk</a>></span> wrote:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr" class=""><div class="">Here's a small reproducer.</div><div class=""><br class=""></div><div class="">struct A {</div><div class=""> virtual void f(...);</div><div class="">};</div><div class=""><br class=""></div><div class="">struct B : virtual A {</div><div class=""> virtual void b();</div><div class=""> virtual void f(...);</div><div class="">};</div><div class=""><br class=""></div><div class="">void B::f(...) {}</div><div class=""><br class=""></div><div class="">$ clang++ -fsanitize=function fsan.cpp -ffunction-sections -fdata-sections -c -o /dev/null<br class=""></div><div class=""><div class="">fatal error: error in backend: Cannot represent a difference across sections</div></div><div class=""><br class=""></div><div class="">Looking at the IR I see this function definition:</div><div class="">define void @_ZTv0_n24_N1B1fEz(%struct.B* %this, ...) unnamed_addr #0 align 2 prologue <{ i32, i32 }> <{ i32 846595819, i32 trunc (i64 sub (i64 ptrtoint (i8** @0 to i64), i64 ptrtoint (void (%struct.B*, ...)* @_ZN1B1fEz to i64)) to i32) }> {<br class=""></div><div class="">which appears to cause the error.</div><div class=""><br class=""></div><div class="">I get basically the same IR if I use a Darwin target triple, so this isn't a Linux-specific issue. (On Darwin we end up successfully creating an object file, but the embedded offset in the text section will presumably be incorrect.)</div><div class=""><br class=""></div><div class="">Note that we're emitting prologue data on virtual functions, which is unnecessary because -fsanitize=function only checks indirect calls via function pointers. So I imagine that one way to solve the problem would be to turn off prologue data emission on non-virtual functions.</div></div></blockquote><div class=""><br class=""></div><div class="">Sorry, I meant "limit prologue data emission to non-virtual functions".</div></div></div></div></div></blockquote><div><br class=""></div><div>That's independently a great idea :).</div><div><br class=""></div><div>I don't see a problem in the IR you've showed above, however. Why do you expect the embedded offset to be incorrect? This program links and runs fine on Darwin:</div><div><br class=""></div><div>---</div><div><div>struct A {</div><div> virtual void f(...) {}</div><div>};</div><div><br class=""></div><div>struct B : virtual A {</div><div> virtual void b() {}</div><div> virtual void f(...);</div><div>};</div><div><br class=""></div><div>void B::f(...) {}</div><div><br class=""></div><div>int main() {</div><div> A a;</div><div> a.f();</div><div><br class=""></div><div> B b;</div><div> b.f();</div><div> b.b();</div><div> return 0;</div><div>}</div><div class="">---</div><div class=""><br class=""></div><div class="">The "Cannot represent difference..." error appears limited to ELF and Wasm, afaik.</div><div class=""><br class=""></div><div class="">vedant</div></div><br class=""><blockquote type="cite" class=""><div class=""><div dir="ltr" class=""><div class="gmail_extra"><div class="gmail_quote"><div class=""><br class=""></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr" class=""><div class="">Peter</div></div><div class="gmail_extra"><div class=""><div class="h5"><br class=""><div class="gmail_quote">On Fri, Oct 13, 2017 at 3:06 PM, Vedant Kumar <span dir="ltr" class=""><<a href="mailto:vsk@apple.com" target="_blank" class="">vsk@apple.com</a>></span> wrote:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="word-wrap:break-word" class=""><br class=""><div class=""><span class=""><blockquote type="cite" class=""><div class="">On Oct 13, 2017, at 2:52 PM, Eric Christopher <<a href="mailto:echristo@gmail.com" target="_blank" class="">echristo@gmail.com</a>> wrote:</div><br class="m_-3309266437497712727m_1661471059887043044Apple-interchange-newline"><div class=""><div dir="ltr" style="font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px" class=""><br class=""><br class=""><div class="gmail_quote"><div dir="ltr" class="">On Fri, Oct 13, 2017 at 2:50 PM Vedant Kumar <<a href="mailto:vsk@apple.com" target="_blank" class="">vsk@apple.com</a>> wrote:<br class=""></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div style="word-wrap:break-word" class=""><div class=""><blockquote type="cite" class=""><div class="">On Oct 13, 2017, at 1:44 PM, Eric Christopher <<a href="mailto:echristo@gmail.com" target="_blank" class="">echristo@gmail.com</a>> wrote:</div><br class="m_-3309266437497712727m_1661471059887043044m_2234658512918948257Apple-interchange-newline"><div class=""><div dir="ltr" class=""><br class=""><br class=""><div class="gmail_quote"><div dir="ltr" class="">On Fri, Oct 13, 2017 at 1:42 PM Vedant Kumar <<a href="mailto:vsk@apple.com" target="_blank" class="">vsk@apple.com</a>> wrote:<br class=""></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div style="word-wrap:break-word" class=""><div class=""><blockquote type="cite" class=""><div class="">On Oct 13, 2017, at 1:39 PM, Vedant Kumar <<a href="mailto:vsk@apple.com" target="_blank" class="">vsk@apple.com</a>> wrote:</div><br class="m_-3309266437497712727m_1661471059887043044m_2234658512918948257m_-5414524569825149145Apple-interchange-newline"><div class=""><div style="word-wrap:break-word" class=""><div class="">Hey Eric,</div><div class=""><br class=""></div><div class="">I'm sorry for the breakage. I made sure to check the run-time tests in compiler-rt but we could have missing coverage there.</div><div class=""><br class=""></div><div class="">The original version of this patch restricted the prologue data changes to Darwin only. We can switch back to that easily, just let me know.</div></div></div></blockquote><div class=""><br class=""></div></div></div><div style="word-wrap:break-word" class=""><div class="">Actually I'll go ahead and work a patch up.</div></div><div style="word-wrap:break-word" class=""><div class=""><br class=""></div></div></blockquote><div class=""><br class=""></div><div class="">Appreciated :)</div><div class=""><br class=""></div><div class="">Basically we were getting an error of:</div><div class=""><br class=""></div><div class=""><span style="color:rgb(33,33,33);font-size:13px" class="">error: Cannot represent a difference across sections</span><br style="color:rgb(33,33,33);font-size:13px" class=""></div><div class=""><span style="color:rgb(33,33,33);font-size:13px" class=""><br class=""></span></div><div class=""><span style="color:rgb(33,33,33);font-size:13px" class="">trying to compile things with the current code.</span></div></div></div></div></blockquote><div class=""><br class=""></div></div></div><div style="word-wrap:break-word" class=""><div class=""><div class="">Oh I see.. well, we started using a difference between the address of a function and the address of a global, so the error makes sense.</div><div class=""><br class=""></div><div class="">I'd be interested in any factors that could narrow the problem down (e.g using a specific linker, using -ffunction-sections, using data-sections, etc). Basically I'm not sure why this would work on some Linux setups but not others.</div><div class=""><br class=""></div></div></div></blockquote><div class=""><br class=""></div><div class="">Definitely using the latter two options and gold as a linker. I'll see what Han can come up with.</div></div></div></div></blockquote><div class=""><br class=""></div></span>Gotcha. Well, -ffunction-sections appears to be untested in compiler-rt/test/ubsan, at least.</div><div class=""><br class=""></div><div class="">There's a test somewhere in there called function.cpp -- it would be great if we could cover the *-sections options there. I'm not sure whether that's what caused the failure, but the extra coverage couldn't hurt :). I would do it myself but I don't have a Linux machine to test on.</div><span class="m_-3309266437497712727HOEnZb"><font color="#888888" class=""><div class=""><br class=""></div><div class="">vedant</div></font></span><div class=""><div class="m_-3309266437497712727h5"><div class=""><br class=""><blockquote type="cite" class=""><div class=""><div dir="ltr" style="font-family:Helvetica;font-size:12px;font-style:normal;font-variant-caps:normal;font-weight:normal;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px" class=""><div class="gmail_quote"><div class=""> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div style="word-wrap:break-word" class=""><div class=""><div class=""></div><div class="">While we figure that out here's a patch to limit the impact on non-Darwin platforms:</div><div class=""><a href="https://reviews.llvm.org/D38903" target="_blank" class="">https://reviews.llvm.org/D3890<wbr class="">3</a></div></div></div></blockquote><div class=""><br class=""></div><div class="">*goes a looking*</div><div class=""><br class=""></div><div class="">Thanks!</div><div class=""><br class=""></div><div class="">-eric </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div style="word-wrap:break-word" class=""><div class=""><div class=""><br class=""></div><div class="">vedant</div></div></div><div style="word-wrap:break-word" class=""><div class=""><br class=""><blockquote type="cite" class=""><div class=""><div dir="ltr" class=""><div class="gmail_quote"><div class=""><span style="color:rgb(33,33,33);font-size:13px" class=""><br class=""></span></div><div class=""><span style="color:rgb(33,33,33);font-size:13px" class="">Thanks!</span></div><div class=""><br class=""></div><div class=""><font color="#212121" class="">-eric</font></div><div class=""> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div style="word-wrap:break-word" class=""><div class=""></div><div class="">vedant</div></div><div style="word-wrap:break-word" class=""><div class=""><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap:break-word" class=""><div class=""><br class=""></div><div class="">vedant</div><div class=""><br class=""></div><br class=""><div class=""><blockquote type="cite" class=""><div class="">On Oct 13, 2017, at 1:33 PM, Eric Christopher <<a href="mailto:echristo@gmail.com" target="_blank" class="">echristo@gmail.com</a>> wrote:</div><br class="m_-3309266437497712727m_1661471059887043044m_2234658512918948257m_-5414524569825149145Apple-interchange-newline"><div class=""><div dir="ltr" class="">Hi Vedant,<div class=""><br class=""></div><div class="">So this actually broke -fsanitize=function on linux. Han is working up a testcase for it, but letting you know for now that we'll probably need some change here.</div><div class=""><br class=""></div><div class="">-eric<br class=""><br class=""><div class="gmail_quote"><div dir="ltr" class="">On Tue, Sep 12, 2017 at 5:05 PM Vedant Kumar via cfe-commits <<a href="mailto:cfe-commits@lists.llvm.org" target="_blank" class="">cfe-commits@lists.llvm.org</a>> wrote:<br class=""></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">Author: vedantk<br class="">Date: Tue Sep 12 17:04:35 2017<br class="">New Revision: 313096<br class=""><br class="">URL:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="http://llvm.org/viewvc/llvm-project?rev=313096&view=rev" rel="noreferrer" target="_blank" class="">http://llvm.org/viewvc/ll<wbr class="">vm-project?rev=313096&view=rev</a><br class="">Log:<br class="">[ubsan] Function Sanitizer: Don't require writable text segments<br class=""><br class="">This change will make it possible to use -fsanitize=function on Darwin and<br class="">possibly on other platforms. It fixes an issue with the way RTTI is stored into<br class="">function prologue data.<br class=""><br class="">On Darwin, addresses stored in prologue data can't require run-time fixups and<br class="">must be PC-relative. Run-time fixups are undesirable because they necessitate<br class="">writable text segments, which can lead to security issues. And absolute<br class="">addresses are undesirable because they break PIE mode.<br class=""><br class="">The fix is to create a private global which points to the RTTI, and then to<br class="">encode a PC-relative reference to the global into prologue data.<br class=""><br class="">Differential Revision:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="https://reviews.llvm.org/D37597" rel="noreferrer" target="_blank" class="">https://reviews.llvm<wbr class="">.org/D37597</a><br class=""><br class="">Modified:<br class=""> <span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span>cfe/trunk/lib/CodeGen/CGExpr<wbr class="">.cpp<br class=""> <span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span>cfe/trunk/lib/CodeGen/CodeGe<wbr class="">nFunction.cpp<br class=""> <span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span>cfe/trunk/lib/CodeGen/CodeGe<wbr class="">nFunction.h<br class=""> <span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span>cfe/trunk/lib/CodeGen/Target<wbr class="">Info.cpp<br class=""> <span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span>cfe/trunk/test/CodeGenCXX/ca<wbr class="">tch-undef-behavior.cpp<br class=""><br class="">Modified: cfe/trunk/lib/CodeGen/CGExpr.c<wbr class="">pp<br class="">URL:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExpr.cpp?rev=313096&r1=313095&r2=313096&view=diff" rel="noreferrer" target="_blank" class="">http://llvm.org/viewvc/ll<wbr class="">vm-project/cfe/trunk/lib/CodeG<wbr class="">en/CGExpr.cpp?rev=313096&r1=<wbr class="">313095&r2=313096&view=diff</a><br class="">==============================<wbr class="">==============================<wbr class="">==================<br class="">--- cfe/trunk/lib/CodeGen/CGExpr.c<wbr class="">pp (original)<br class="">+++ cfe/trunk/lib/CodeGen/CGExpr.c<wbr class="">pp Tue Sep 12 17:04:35 2017<br class="">@@ -4409,10 +4409,7 @@ RValue CodeGenFunction::EmitCall(Qual<wbr class="">Typ<br class=""> SanitizerScope SanScope(this);<br class=""> llvm::Constant *FTRTTIConst =<br class=""> CGM.GetAddrOfRTTIDescriptor(Q<wbr class="">ualType(FnType, 0), /*ForEH=*/true);<br class="">- llvm::Type *PrefixStructTyElems[] = {<br class="">- PrefixSig->getType(),<br class="">- FTRTTIConst->getType()<br class="">- };<br class="">+ llvm::Type *PrefixStructTyElems[] = {PrefixSig->getType(), Int32Ty};<br class=""> llvm::StructType *PrefixStructTy = llvm::StructType::get(<br class=""> CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);<br class=""><br class="">@@ -4433,8 +4430,10 @@ RValue CodeGenFunction::EmitCall(Qual<wbr class="">Typ<br class=""> EmitBlock(TypeCheck);<br class=""> llvm::Value *CalleeRTTIPtr =<br class=""> Builder.CreateConstGEP2_32(Pr<wbr class="">efixStructTy, CalleePrefixStruct, 0, 1);<br class="">- llvm::Value *CalleeRTTI =<br class="">+ llvm::Value *CalleeRTTIEncoded =<br class=""> Builder.CreateAlignedLoad(Cal<wbr class="">leeRTTIPtr, getPointerAlign());<br class="">+ llvm::Value *CalleeRTTI =<br class="">+ DecodeAddrUsedInPrologue(Calle<wbr class="">ePtr, CalleeRTTIEncoded);<br class=""> llvm::Value *CalleeRTTIMatch =<br class=""> Builder.CreateICmpEQ(CalleeRT<wbr class="">TI, FTRTTIConst);<br class=""> llvm::Constant *StaticData[] = {<br class=""><br class="">Modified: cfe/trunk/lib/CodeGen/CodeGenF<wbr class="">unction.cpp<br class="">URL:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.cpp?rev=313096&r1=313095&r2=313096&view=diff" rel="noreferrer" target="_blank" class="">http://llvm.org/viewvc/ll<wbr class="">vm-project/cfe/trunk/lib/CodeG<wbr class="">en/CodeGenFunction.cpp?rev=<wbr class="">313096&r1=313095&r2=313096&<wbr class="">view=diff</a><br class="">==============================<wbr class="">==============================<wbr class="">==================<br class="">--- cfe/trunk/lib/CodeGen/CodeGenF<wbr class="">unction.cpp (original)<br class="">+++ cfe/trunk/lib/CodeGen/CodeGenF<wbr class="">unction.cpp Tue Sep 12 17:04:35 2017<br class="">@@ -429,6 +429,43 @@ bool CodeGenFunction::ShouldXRayIns<wbr class="">trume<br class=""> return CGM.getCodeGenOpts().XRayInstr<wbr class="">umentFunctions;<br class=""> }<br class=""><br class="">+llvm::Constant *<br class="">+CodeGenFunction::EncodeAddrFo<wbr class="">rUseInPrologue(llvm::Function *F,<br class="">+ llvm::Constant *Addr) {<br class="">+ // Addresses stored in prologue data can't require run-time fixups and must<br class="">+ // be PC-relative. Run-time fixups are undesirable because they necessitate<br class="">+ // writable text segments, which are unsafe. And absolute addresses are<br class="">+ // undesirable because they break PIE mode.<br class="">+<br class="">+ // Add a layer of indirection through a private global. Taking its address<br class="">+ // won't result in a run-time fixup, even if Addr has linkonce_odr linkage.<br class="">+ auto *GV = new llvm::GlobalVariable(CGM.getMo<wbr class="">dule(), Addr->getType(),<br class="">+ /*isConstant=*/true,<br class="">+ llvm::GlobalValue::PrivateLink<wbr class="">age, Addr);<br class="">+<br class="">+ // Create a PC-relative address.<br class="">+ auto *GOTAsInt = llvm::ConstantExpr::getPtrToIn<wbr class="">t(GV, IntPtrTy);<br class="">+ auto *FuncAsInt = llvm::ConstantExpr::getPtrToIn<wbr class="">t(F, IntPtrTy);<br class="">+ auto *PCRelAsInt = llvm::ConstantExpr::getSub(GOT<wbr class="">AsInt, FuncAsInt);<br class="">+ return (IntPtrTy == Int32Ty)<br class="">+ ? PCRelAsInt<br class="">+ : llvm::ConstantExpr::getTrunc(P<wbr class="">CRelAsInt, Int32Ty);<br class="">+}<br class="">+<br class="">+llvm::Value *<br class="">+CodeGenFunction::DecodeAddrUs<wbr class="">edInPrologue(llvm::Value *F,<br class="">+ llvm::Value *EncodedAddr) {<br class="">+ // Reconstruct the address of the global.<br class="">+ auto *PCRelAsInt = Builder.CreateSExt(EncodedAddr<wbr class="">, IntPtrTy);<br class="">+ auto *FuncAsInt = Builder.CreatePtrToInt(F, IntPtrTy, "<a href="http://func_addr.int/" rel="noreferrer" target="_blank" class="">func_addr.int</a>");<br class="">+ auto *GOTAsInt = Builder.CreateAdd(PCRelAsInt, FuncAsInt, "<a href="http://global_addr.int/" rel="noreferrer" target="_blank" class="">global_addr.int</a>");<br class="">+ auto *GOTAddr = Builder.CreateIntToPtr(GOTAsIn<wbr class="">t, Int8PtrPtrTy, "global_addr");<br class="">+<br class="">+ // Load the original pointer through the global.<br class="">+ return Builder.CreateLoad(Address(GOT<wbr class="">Addr, getPointerAlign()),<br class="">+ "decoded_addr");<br class="">+}<br class="">+<br class=""> /// EmitFunctionInstrumentation - Emit LLVM code to call the specified<br class=""> /// instrumentation function with the current function and the call site, if<br class=""> /// function instrumentation is enabled.<br class="">@@ -856,7 +893,10 @@ void CodeGenFunction::StartFunction<wbr class="">(Glob<br class=""> CGM.getTargetCodeGenInfo().ge<wbr class="">tUBSanFunctionSignature(CGM)) {<br class=""> llvm::Constant *FTRTTIConst =<br class=""> CGM.GetAddrOfRTTIDescriptor(F<wbr class="">D->getType(), /*ForEH=*/true);<br class="">- llvm::Constant *PrologueStructElems[] = { PrologueSig, FTRTTIConst };<br class="">+ llvm::Constant *FTRTTIConstEncoded =<br class="">+ EncodeAddrForUseInPrologue(Fn, FTRTTIConst);<br class="">+ llvm::Constant *PrologueStructElems[] = {PrologueSig,<br class="">+ FTRTTIConstEncoded};<br class=""> llvm::Constant *PrologueStructConst =<br class=""> llvm::ConstantStruct::getAnon<wbr class="">(PrologueStructElems, /*Packed=*/true);<br class=""> Fn->setPrologueData(PrologueS<wbr class="">tructConst);<br class=""><br class="">Modified: cfe/trunk/lib/CodeGen/CodeGenF<wbr class="">unction.h<br class="">URL:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=313096&r1=313095&r2=313096&view=diff" rel="noreferrer" target="_blank" class="">http://llvm.org/viewvc/ll<wbr class="">vm-project/cfe/trunk/lib/CodeG<wbr class="">en/CodeGenFunction.h?rev=31309<wbr class="">6&r1=313095&r2=313096&view=<wbr class="">diff</a><br class="">==============================<wbr class="">==============================<wbr class="">==================<br class="">--- cfe/trunk/lib/CodeGen/CodeGenF<wbr class="">unction.h (original)<br class="">+++ cfe/trunk/lib/CodeGen/CodeGenF<wbr class="">unction.h Tue Sep 12 17:04:35 2017<br class="">@@ -1776,6 +1776,15 @@ public:<br class=""> /// EmitMCountInstrumentation - Emit call to .mcount.<br class=""> void EmitMCountInstrumentation();<br class=""><br class="">+ /// Encode an address into a form suitable for use in a function prologue.<br class="">+ llvm::Constant *EncodeAddrForUseInPrologue(ll<wbr class="">vm::Function *F,<br class="">+ llvm::Constant *Addr);<br class="">+<br class="">+ /// Decode an address used in a function prologue, encoded by \c<br class="">+ /// EncodeAddrForUseInPrologue.<br class="">+ llvm::Value *DecodeAddrUsedInPrologue(llvm<wbr class="">::Value *F,<br class="">+ llvm::Value *EncodedAddr);<br class="">+<br class=""> /// EmitFunctionProlog - Emit the target specific LLVM code to load the<br class=""> /// arguments for the given function. This is also responsible for naming the<br class=""> /// LLVM function arguments.<br class=""><br class="">Modified: cfe/trunk/lib/CodeGen/TargetIn<wbr class="">fo.cpp<br class="">URL:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/TargetInfo.cpp?rev=313096&r1=313095&r2=313096&view=diff" rel="noreferrer" target="_blank" class="">http://llvm.org/viewvc/ll<wbr class="">vm-project/cfe/trunk/lib/CodeG<wbr class="">en/TargetInfo.cpp?rev=313096&<wbr class="">r1=313095&r2=313096&view=diff</a><br class="">==============================<wbr class="">==============================<wbr class="">==================<br class="">--- cfe/trunk/lib/CodeGen/TargetIn<wbr class="">fo.cpp (original)<br class="">+++ cfe/trunk/lib/CodeGen/TargetIn<wbr class="">fo.cpp Tue Sep 12 17:04:35 2017<br class="">@@ -1086,8 +1086,8 @@ public:<br class=""> getUBSanFunctionSignature(Cod<wbr class="">eGen::CodeGenModule &CGM) const override {<br class=""> unsigned Sig = (0xeb << 0) | // jmp rel8<br class=""> <span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span>(0x06 << 8) | // .+0x08<br class="">- ('F' << 16) |<br class="">- ('T' << 24);<br class="">+ ('v' << 16) |<br class="">+ ('2' << 24);<br class=""> return llvm::ConstantInt::get(CGM.Int<wbr class="">32Ty, Sig);<br class=""> }<br class=""><br class="">@@ -2277,17 +2277,10 @@ public:<br class=""><br class=""> llvm::Constant *<br class=""> getUBSanFunctionSignature(Cod<wbr class="">eGen::CodeGenModule &CGM) const override {<br class="">- unsigned Sig;<br class="">- if (getABIInfo().has64BitPointers<wbr class="">())<br class="">- Sig = (0xeb << 0) | // jmp rel8<br class="">- (0x0a << 8) | // .+0x0c<br class="">- ('F' << 16) |<br class="">- ('T' << 24);<br class="">- else<br class="">- Sig = (0xeb << 0) | // jmp rel8<br class="">- (0x06 << 8) | // .+0x08<br class="">- ('F' << 16) |<br class="">- ('T' << 24);<br class="">+ unsigned Sig = (0xeb << 0) | // jmp rel8<br class="">+ (0x06 << 8) | // .+0x08<br class="">+ ('v' << 16) |<br class="">+ ('2' << 24);<br class=""> return llvm::ConstantInt::get(CGM.Int<wbr class="">32Ty, Sig);<br class=""> }<br class=""><br class=""><br class="">Modified: cfe/trunk/test/CodeGenCXX/catc<wbr class="">h-undef-behavior.cpp<br class="">URL:<span class="m_-3309266437497712727m_1661471059887043044Apple-converted-space"> </span><a href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/catch-undef-behavior.cpp?rev=313096&r1=313095&r2=313096&view=diff" rel="noreferrer" target="_blank" class="">http://llvm.org/viewvc/ll<wbr class="">vm-project/cfe/trunk/test/Code<wbr class="">GenCXX/catch-undef-behavior.<wbr class="">cpp?rev=313096&r1=313095&r2=<wbr class="">313096&view=diff</a><br class="">==============================<wbr class="">==============================<wbr class="">==================<br class="">--- cfe/trunk/test/CodeGenCXX/catc<wbr class="">h-undef-behavior.cpp (original)<br class="">+++ cfe/trunk/test/CodeGenCXX/catc<wbr class="">h-undef-behavior.cpp Tue Sep 12 17:04:35 2017<br class="">@@ -16,6 +16,10 @@ struct S {<br class=""> // Check that type mismatch handler is not modified by ASan.<br class=""> // CHECK-ASAN: private unnamed_addr global { { [{{.*}} x i8]*, i32, i32 }, { i16, i16, [4 x i8] }*, i8*, i8 } { {{.*}}, { i16, i16, [4 x i8] }* [[TYPE_DESCR]], {{.*}} }<br class=""><br class="">+// CHECK: [[IndirectRTTI_ZTIFvPFviEE:@.+<wbr class="">]] = private constant i8* bitcast ({ i8*, i8* }* @_ZTIFvPFviEE to i8*)<br class="">+// CHECK-X86: [[IndirectRTTI_ZTIFvPFviEE:@.+<wbr class="">]] = private constant i8* bitcast ({ i8*, i8* }* @_ZTIFvPFviEE to i8*)<br class="">+// CHECK-X32: [[IndirectRTTI_ZTIFvPFviEE:@.+<wbr class="">]] = private constant i8* bitcast ({ i8*, i8* }* @_ZTIFvPFviEE to i8*)<br class="">+<br class=""> struct T : S {};<br class=""><br class=""> // CHECK-LABEL: @_Z17reference_binding<br class="">@@ -395,23 +399,30 @@ void downcast_reference(B &b) {<br class=""> // CHECK-NEXT: br i1 [[AND]]<br class=""> }<br class=""><br class="">-// CHECK-LABEL: @_Z22indirect_function_callPFv<wbr class="">iE({{.*}} prologue <{ i32, i8* }> <{ i32 1413876459, i8* bitcast ({ i8*, i8* }* @_ZTIFvPFviEE to i8*) }><br class="">-// CHECK-X32: @_Z22indirect_function_callPFv<wbr class="">iE({{.*}} prologue <{ i32, i8* }> <{ i32 1413875435, i8* bitcast ({ i8*, i8* }* @_ZTIFvPFviEE to i8*) }><br class="">-// CHECK-X86: @_Z22indirect_function_callPFv<wbr class="">iE({{.*}} prologue <{ i32, i8* }> <{ i32 1413875435, i8* bitcast ({ i8*, i8* }* @_ZTIFvPFviEE to i8*) }><br class="">+//<br class="">+// CHECK-LABEL: @_Z22indirect_function_callPFv<wbr class="">iE({{.*}} prologue <{ i32, i32 }> <{ i32 846595819, i32 trunc (i64 sub (i64 ptrtoint (i8** {{.*}} to i64), i64 ptrtoint (void (void (i32)*)* @_Z22indirect_function_callPFv<wbr class="">iE to i64)) to i32) }><br class="">+// CHECK-X32: @_Z22indirect_function_callPFv<wbr class="">iE({{.*}} prologue <{ i32, i32 }> <{ i32 846595819, i32 sub (i32 ptrtoint (i8** [[IndirectRTTI_ZTIFvPFviEE]] to i32), i32 ptrtoint (void (void (i32)*)* @_Z22indirect_function_callPFv<wbr class="">iE to i32)) }><br class="">+// CHECK-X86: @_Z22indirect_function_callPFv<wbr class="">iE({{.*}} prologue <{ i32, i32 }> <{ i32 846595819, i32 sub (i32 ptrtoint (i8** [[IndirectRTTI_ZTIFvPFviEE]] to i32), i32 ptrtoint (void (void (i32)*)* @_Z22indirect_function_callPFv<wbr class="">iE to i32)) }><br class=""> void indirect_function_call(void (*p)(int)) {<br class="">- // CHECK: [[PTR:%.+]] = bitcast void (i32)* {{.*}} to <{ i32, i8* }>*<br class="">+ // CHECK: [[PTR:%.+]] = bitcast void (i32)* {{.*}} to <{ i32, i32 }>*<br class=""><br class=""> // Signature check<br class="">- // CHECK-NEXT: [[SIGPTR:%.+]] = getelementptr <{ i32, i8* }>, <{ i32, i8* }>* [[PTR]], i32 0, i32 0<br class="">+ // CHECK-NEXT: [[SIGPTR:%.+]] = getelementptr <{ i32, i32 }>, <{ i32, i32 }>* [[PTR]], i32 0, i32 0<br class=""> // CHECK-NEXT: [[SIG:%.+]] = load i32, i32* [[SIGPTR]]<br class="">- // CHECK-NEXT: [[SIGCMP:%.+]] = icmp eq i32 [[SIG]], 1413876459<br class="">+ // CHECK-NEXT: [[SIGCMP:%.+]] = icmp eq i32 [[SIG]], 846595819<br class=""> // CHECK-NEXT: br i1 [[SIGCMP]]<br class=""><br class=""> // RTTI pointer check<br class="">- // CHECK: [[RTTIPTR:%.+]] = getelementptr <{ i32, i8* }>, <{ i32, i8* }>* [[PTR]], i32 0, i32 1<br class="">- // CHECK-NEXT: [[RTTI:%.+]] = load i8*, i8** [[RTTIPTR]]<br class="">+ // CHECK: [[RTTIPTR:%.+]] = getelementptr <{ i32, i32 }>, <{ i32, i32 }>* [[PTR]], i32 0, i32 1<br class="">+ // CHECK-NEXT: [[RTTIEncIntTrunc:%.+]] = load i32, i32* [[RTTIPTR]]<br class="">+ // CHECK-NEXT: [[RTTIEncInt:%.+]] = sext i32 [[RTTIEncIntTrunc]] to i64<br class="">+ // CHECK-NEXT: [[FuncAddrInt:%.+]] = ptrtoint void (i32)* {{.*}} to i64<br class="">+ // CHECK-NEXT: [[IndirectGVInt:%.+]] = add i64 [[RTTIEncInt]], [[FuncAddrInt]]<br class="">+ // CHECK-NEXT: [[IndirectGV:%.+]] = inttoptr i64 [[IndirectGVInt]] to i8**<br class="">+ // CHECK-NEXT: [[RTTI:%.+]] = load i8*, i8** [[IndirectGV]], align 8<br class=""> // CHECK-NEXT: [[RTTICMP:%.+]] = icmp eq i8* [[RTTI]], bitcast ({ i8*, i8* }* @_ZTIFviE to i8*)<br class=""> // CHECK-NEXT: br i1 [[RTTICMP]]<br class="">+<br class=""> p(42);<br class=""> }<br class=""><br class=""><br class=""><br class="">______________________________<wbr class="">_________________<br class="">cfe-commits mailing list<br class=""><a href="mailto:cfe-commits@lists.llvm.org" target="_blank" class="">cfe-commits@lists.llvm.org</a><br class=""><a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits" rel="noreferrer" target="_blank" class="">http://lists.llvm.org/cgi-bin/<wbr class="">mailman/listinfo/cfe-commits</a></blockquote></div></div></div></div></blockquote></div></div></div></blockquote></div></div></blockquote></div></div></div></blockquote></div></div></blockquote></div></div></div></blockquote></div><br class=""></div></div></div></blockquote></div><br class=""><br clear="all" class=""><div class=""><br class=""></div></div></div><span class="HOEnZb"><font color="#888888" class="">-- <br class=""><div class="m_-3309266437497712727gmail_signature" data-smartmail="gmail_signature"><div dir="ltr" class="">-- <div class="">Peter</div></div></div>
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</blockquote></div><br class=""><br clear="all" class=""><div class=""><br class=""></div>-- <br class=""><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr" class="">-- <div class="">Peter</div></div></div>
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