6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-17 03:30:28 +00:00
Code Issues Projects Releases Wiki Activity

Now that instruction optzns can update the iterator as they go, we can

Browse Source 
have objectsize folding recursively simplify away their result when it
folds.  It is important to catch this here, because otherwise we won't
eliminate the cross-block values at isel and other times.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123524 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2011-01-15 07:25:29 +00:00
parent 7579609bfe
commit 94e8e0cfbe
2 changed files with 40 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
lib/Transforms/Scalar/CodeGenPrepare.cpp
View File

@ -42,6 +42,7 @@
#include "llvm/Support/PatternMatch.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/IRBuilder.h"
#include "llvm/Support/ValueHandle.h"
using namespace llvm;
using namespace llvm::PatternMatch;
@ -634,8 +635,18 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
bool Min = (cast<ConstantInt>(II->getArgOperand(1))->getZExtValue() == 1);
const Type *ReturnTy = CI->getType();
Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);
CI->replaceAllUsesWith(RetVal);
CI->eraseFromParent();
// Substituting this can cause recursive simplifications, which can
// invalidate our iterator. Use a WeakVH to hold onto it in case this
// happens.
WeakVH IterHandle(CurInstIterator);
ReplaceAndSimplifyAllUses(CI, RetVal, TLI ? TLI->getTargetData() : 0, DT);
// If the iterator instruction was recursively deleted, start over at the
// start of the block.
if (IterHandle != CurInstIterator)
CurInstIterator = BB->begin();
return true;
}
@ -653,6 +664,7 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
CodeGenPrepareFortifiedLibCalls Simplifier;
return Simplifier.fold(CI, TD);
}
//===----------------------------------------------------------------------===//
// Memory Optimization
//===----------------------------------------------------------------------===//
@ -1076,14 +1088,8 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
SunkAddrs.clear();
CurInstIterator = BB.begin();
for (BasicBlock::iterator E = BB.end(); CurInstIterator != E; ) {
Instruction *I = CurInstIterator++;
if (CallInst *CI = dyn_cast<CallInst>(I))
MadeChange |= OptimizeCallInst(CI);
else
MadeChange |= OptimizeInst(I);
}
for (BasicBlock::iterator E = BB.end(); CurInstIterator != E; )
MadeChange |= OptimizeInst(CurInstIterator++);
return MadeChange;
}

24
test/Transforms/CodeGenPrepare/basic.ll Normal file
View File

@ -0,0 +1,24 @@
; RUN: opt -codegenprepare %s -S -o - | 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-darwin10.0.0"
; CHECK: @test1
define i32 @test1(i8* %ptr) nounwind ssp noredzone align 2 {
entry:
%0 = tail call i64 @llvm.objectsize.i64(i8* %ptr, i1 false)
%1 = icmp ugt i64 %0, 3
br i1 %1, label %T, label %trap
; CHECK: br i1 true, label
trap: ; preds = %0, %entry
tail call void @llvm.trap() noreturn nounwind
unreachable
T:
ret i32 4
}
declare i64 @llvm.objectsize.i64(i8*, i1) nounwind readonly
declare void @llvm.trap() nounwind