6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-28 19:31:58 +00:00
Code Issues Projects Releases Wiki Activity

In the default address space, any GEP off of null results in a trap value if you try to load it. Thus,

Browse Source 
any load in the default address space that completes implies that the base value that it GEP'd from
was not null.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112015 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2010-08-25 01:16:47 +00:00
parent a2c9188560
commit 6cd2075549
2 changed files with 53 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
lib/Analysis/LazyValueInfo.cpp
View File

@ -457,10 +457,11 @@ LVILatticeVal LVIQuery::getBlockValue(BasicBlock *BB) {
// then we know that the pointer can't be NULL.
if (Val->getType()->isPointerTy()) {
const PointerType *PTy = cast<PointerType>(Val->getType());
for (Value::use_iterator UI = Val->use_begin(), UE = Val->use_end();
UI != UE; ++UI) {
LoadInst *L = dyn_cast<LoadInst>(*UI);
if (L && L->getParent() == BB && L->getPointerAddressSpace() == 0) {
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end();BI != BE;++BI){
LoadInst *L = dyn_cast<LoadInst>(BI);
if (L && L->getPointerAddressSpace() == 0 &&
L->getPointerOperand()->getUnderlyingObject() ==
Val->getUnderlyingObject()) {
return LVILatticeVal::getNot(ConstantPointerNull::get(PTy));
}
}

48
test/Transforms/JumpThreading/lvi-load.ll Normal file
View File

@ -0,0 +1,48 @@
; RUN: opt -S -jump-threading -enable-jump-threading-lvi < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-darwin10.4"
%"struct.llvm::PATypeHolder" = type { %"struct.llvm::Type"* }
%"struct.llvm::PointerIntPair<llvm::Use**,2u,llvm::Use::PrevPtrTag,llvm::PointerLikeTypeTraits<llvm::Use**> >" = type { i64 }
%"struct.llvm::Type" = type opaque
%"struct.llvm::Use" = type { %"struct.llvm::Value"*, %"struct.llvm::Use"*, %"struct.llvm::PointerIntPair<llvm::Use**,2u,llvm::Use::PrevPtrTag,llvm::PointerLikeTypeTraits<llvm::Use**> >" }
%"struct.llvm::Value" = type { i32 (...)**, i8, i8, i16, %"struct.llvm::PATypeHolder", %"struct.llvm::Use"*, %"struct.llvm::ValueName"* }
%"struct.llvm::ValueName" = type opaque
@_ZZN4llvm4castINS_11InstructionEPNS_5ValueEEENS_10cast_rettyIT_T0_E8ret_typeERKS6_E8__func__ = internal constant [5 x i8] c"cast\00", align 8 ; <[5 x i8]*> [#uses=1]
@.str = private constant [31 x i8] c"include/llvm/Support/Casting.h\00", align 8 ; <[31 x i8]*> [#uses=1]
@.str1 = private constant [59 x i8] c"isa<X>(Val) && \22cast<Ty>() argument of incompatible type!\22\00", align 8 ; <[59 x i8]*> [#uses=1]
; CHECK: Z3fooPN4llvm5ValueE
define zeroext i8 @_Z3fooPN4llvm5ValueE(%"struct.llvm::Value"* %V) ssp {
entry:
%0 = getelementptr inbounds %"struct.llvm::Value"* %V, i64 0, i32 1 ; <i8*> [#uses=1]
%1 = load i8* %0, align 8 ; <i8> [#uses=2]
%2 = icmp ugt i8 %1, 20 ; <i1> [#uses=1]
br i1 %2, label %bb.i, label %bb2
bb.i: ; preds = %entry
%toBoolnot.i.i = icmp ult i8 %1, 21 ; <i1> [#uses=1]
br i1 %toBoolnot.i.i, label %bb6.i.i, label %_ZN4llvm8dyn_castINS_11InstructionEPNS_5ValueEEENS_10cast_rettyIT_T0_E8ret_typeERKS6_.exit
bb6.i.i: ; preds = %bb.i
tail call void @__assert_rtn(i8* getelementptr inbounds ([5 x i8]* @_ZZN4llvm4castINS_11InstructionEPNS_5ValueEEENS_10cast_rettyIT_T0_E8ret_typeERKS6_E8__func__, i64 0, i64 0), i8* getelementptr inbounds ([31 x i8]* @.str, i64 0, i64 0), i32 202, i8* getelementptr inbounds ([59 x i8]* @.str1, i64 0, i64 0)) noreturn
unreachable
_ZN4llvm8dyn_castINS_11InstructionEPNS_5ValueEEENS_10cast_rettyIT_T0_E8ret_typeERKS6_.exit: ; preds = %bb.i
; CHECK-NOT: null
%3 = icmp eq %"struct.llvm::Value"* %V, null ; <i1> [#uses=1]
br i1 %3, label %bb2, label %bb
bb: ; preds = %_ZN4llvm8dyn_castINS_11InstructionEPNS_5ValueEEENS_10cast_rettyIT_T0_E8ret_typeERKS6_.exit
tail call void @_ZNK4llvm5Value4dumpEv(%"struct.llvm::Value"* %V)
; CHECK: ret
ret i8 1
bb2: ; preds = %entry, %_ZN4llvm8dyn_castINS_11InstructionEPNS_5ValueEEENS_10cast_rettyIT_T0_E8ret_typeERKS6_.exit
ret i8 0
}
declare void @__assert_rtn(i8*, i8*, i32, i8*) noreturn
declare void @_ZNK4llvm5Value4dumpEv(%"struct.llvm::Value"*)