6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-08-22 10:29:35 +00:00
Code Issues Projects Releases Wiki Activity

Make instcombine ensure that all allocas are explicitly aligned at at

Browse Source 
least their preferred alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62176 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2009-01-13 20:18:38 +00:00
parent 1b04694116
commit 6893cd7615
3 changed files with 15 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
lib/Transforms/Scalar/InstructionCombining.cpp
View File

@ -10775,12 +10775,17 @@ Instruction *InstCombiner::visitAllocationInst(AllocationInst &AI) {
}
}
// If alloca'ing a zero byte object, replace the alloca with a null pointer.
// Note that we only do this for alloca's, because malloc should allocate and
// return a unique pointer, even for a zero byte allocation.
if (isa<AllocaInst>(AI) && AI.getAllocatedType()->isSized() &&
TD->getTypePaddedSize(AI.getAllocatedType()) == 0)
return ReplaceInstUsesWith(AI, Constant::getNullValue(AI.getType()));
if (isa<AllocaInst>(AI) && AI.getAllocatedType()->isSized()) {
// If alloca'ing a zero byte object, replace the alloca with a null pointer.
// Note that we only do this for alloca's, because malloc should allocate and
// return a unique pointer, even for a zero byte allocation.
if (TD->getTypePaddedSize(AI.getAllocatedType()) == 0)
return ReplaceInstUsesWith(AI, Constant::getNullValue(AI.getType()));
// If the alignment is 0 (unspecified), assign it the preferred alignment.
if (AI.getAlignment() == 0)
AI.setAlignment(TD->getPrefTypeAlignment(AI.getAllocatedType()));
}
return 0;
}

4
test/Transforms/InstCombine/2009-01-08-AlignAlloca.ll
View File

@ -1,4 +1,6 @@
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {, align 4} | count 4
; RUN: llvm-as < %s | opt -instcombine | llvm-dis > %t
; RUN: grep {, align 4} %t | count 3
; RUN: grep {, align 8} %t | count 3
; rdar://6480438
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
target triple = "i386-apple-darwin9.6"

2
test/Transforms/InstCombine/loadstore-alignment.ll
View File

@ -1,4 +1,4 @@
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {, align 16} | count 12
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep {, align 16} | count 14
@x = external global <2 x i64>, align 16
@xx = external global [13 x <2 x i64>], align 16