6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-03-02 07:30:52 +00:00
Code Issues Projects Releases Wiki Activity

PR7959: Handle negative scales in GEPs correctly in BasicAA for non-64-bit

Browse Source 
targets.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114015 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eli Friedman 2010-09-15 20:08:03 +00:00
parent f1c3eb37ae
commit 39e30124e5
2 changed files with 18 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
lib/Analysis/BasicAliasAnalysis.cpp
View File

@ -386,8 +386,8 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
// The GEP index scale ("Scale") scales C1*V+C2, yielding (C1*V+C2)*Scale. // The GEP index scale ("Scale") scales C1*V+C2, yielding (C1*V+C2)*Scale.
// This gives us an aggregate computation of (C1*Scale)*V + C2*Scale. // This gives us an aggregate computation of (C1*Scale)*V + C2*Scale.
BaseOffs += IndexOffset.getZExtValue()*Scale; BaseOffs += IndexOffset.getSExtValue()*Scale;
Scale *= IndexScale.getZExtValue(); Scale *= IndexScale.getSExtValue();
// If we already had an occurrance of this index variable, merge this // If we already had an occurrance of this index variable, merge this
@ -407,7 +407,7 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
// pointer size. // pointer size.
if (unsigned ShiftBits = 64-TD->getPointerSizeInBits()) { if (unsigned ShiftBits = 64-TD->getPointerSizeInBits()) {
Scale <<= ShiftBits; Scale <<= ShiftBits;
Scale >>= ShiftBits; Scale = (int64_t)Scale >> ShiftBits;
} }
if (Scale) { if (Scale) {

15
test/Analysis/BasicAA/2010-09-15-GEP-SignedArithmetic.ll Normal file
View File

@ -0,0 +1,15 @@
; RUN: opt < %s -basicaa -aa-eval -print-all-alias-modref-info -disable-output |& grep {1 may alias}
; PR7959
target datalayout = "e-p:32:32:32"
define i32 @test(i32* %tab, i32 %indvar) nounwind {
%tmp31 = mul i32 %indvar, -2
%tmp32 = add i32 %tmp31, 30
%t.5 = getelementptr i32* %tab, i32 %tmp32
%loada = load i32* %tab
store i32 0, i32* %t.5
%loadb = load i32* %tab
%rval = add i32 %loada, %loadb
ret i32 %rval
}