From 5f4899dbfe37eba1c460b27b761bd457cfadd508 Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Sat, 4 Jul 2015 20:07:37 +0000 Subject: [PATCH] Pull in r241142 from upstream llvm trunk (by David Majnemer): [SCCP] Turn loads of null into undef instead of zero initialized values Surprisingly, this is a correctness issue: the mmx type exists for calling convention purposes, LLVM doesn't have a zero representation for them. This partially fixes PR23999. Pull in r241143 from upstream llvm trunk (by David Majnemer): [LoopUnroll] Use undef for phis with no value live We would create a phi node with a zero initialized operand instead of undef in the case where no value was originally available. This was problematic for x86_mmx which has no null value. These fix a "Cannot create a null constant of that type!" error when compiling the graphics/sdl2_gfx port with MMX enabled. Reported by: amdmi3 --- contrib/llvm/lib/Transforms/Scalar/SCCP.cpp | 2 +- contrib/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/contrib/llvm/lib/Transforms/Scalar/SCCP.cpp b/contrib/llvm/lib/Transforms/Scalar/SCCP.cpp index cfc9a8e89fa..e0e314a4328 100644 --- a/contrib/llvm/lib/Transforms/Scalar/SCCP.cpp +++ b/contrib/llvm/lib/Transforms/Scalar/SCCP.cpp @@ -1054,7 +1054,7 @@ void SCCPSolver::visitLoadInst(LoadInst &I) { // load null -> null if (isa(Ptr) && I.getPointerAddressSpace() == 0) - return markConstant(IV, &I, Constant::getNullValue(I.getType())); + return markConstant(IV, &I, UndefValue::get(I.getType())); // Transform load (constant global) into the value loaded. if (GlobalVariable *GV = dyn_cast(Ptr)) { diff --git a/contrib/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp b/contrib/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp index 8a32215a299..db4a5c1e5b7 100644 --- a/contrib/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp +++ b/contrib/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp @@ -81,7 +81,7 @@ static void ConnectProlog(Loop *L, Value *BECount, unsigned Count, if (L->contains(PN)) { NewPN->addIncoming(PN->getIncomingValueForBlock(NewPH), OrigPH); } else { - NewPN->addIncoming(Constant::getNullValue(PN->getType()), OrigPH); + NewPN->addIncoming(UndefValue::get(PN->getType()), OrigPH); } Value *V = PN->getIncomingValueForBlock(Latch);