[polly] r285746 - [ScopInfo] Make memset etc. affine where possible.
Eli Friedman via llvm-commits
llvm-commits at lists.llvm.org
Tue Nov 1 13:53:11 PDT 2016
Author: efriedma
Date: Tue Nov 1 15:53:11 2016
New Revision: 285746
URL: http://llvm.org/viewvc/llvm-project?rev=285746&view=rev
Log:
[ScopInfo] Make memset etc. affine where possible.
We don't actually check whether a MemoryAccess is affine in very many
places, but one important one is in checks for aliasing.
Differential Revision: https://reviews.llvm.org/D25706
Modified:
polly/trunk/lib/Analysis/ScopBuilder.cpp
polly/trunk/lib/Analysis/ScopInfo.cpp
polly/trunk/test/ScopInfo/aliasing_with_non_affine_access.ll
Modified: polly/trunk/lib/Analysis/ScopBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Analysis/ScopBuilder.cpp?rev=285746&r1=285745&r2=285746&view=diff
==============================================================================
--- polly/trunk/lib/Analysis/ScopBuilder.cpp (original)
+++ polly/trunk/lib/Analysis/ScopBuilder.cpp Tue Nov 1 15:53:11 2016
@@ -275,8 +275,9 @@ bool ScopBuilder::buildAccessMemIntrinsi
assert(DestPtrSCEV);
DestAccFunc = SE.getMinusSCEV(DestAccFunc, DestPtrSCEV);
addArrayAccess(Inst, MemoryAccess::MUST_WRITE, DestPtrSCEV->getValue(),
- IntegerType::getInt8Ty(DestPtrVal->getContext()), false,
- {DestAccFunc, LengthVal}, {nullptr}, Inst.getValueOperand());
+ IntegerType::getInt8Ty(DestPtrVal->getContext()),
+ LengthIsAffine, {DestAccFunc, LengthVal}, {nullptr},
+ Inst.getValueOperand());
auto *MemTrans = dyn_cast<MemTransferInst>(MemIntr);
if (!MemTrans)
@@ -296,8 +297,9 @@ bool ScopBuilder::buildAccessMemIntrinsi
assert(SrcPtrSCEV);
SrcAccFunc = SE.getMinusSCEV(SrcAccFunc, SrcPtrSCEV);
addArrayAccess(Inst, MemoryAccess::READ, SrcPtrSCEV->getValue(),
- IntegerType::getInt8Ty(SrcPtrVal->getContext()), false,
- {SrcAccFunc, LengthVal}, {nullptr}, Inst.getValueOperand());
+ IntegerType::getInt8Ty(SrcPtrVal->getContext()),
+ LengthIsAffine, {SrcAccFunc, LengthVal}, {nullptr},
+ Inst.getValueOperand());
return true;
}
Modified: polly/trunk/lib/Analysis/ScopInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/Analysis/ScopInfo.cpp?rev=285746&r1=285745&r2=285746&view=diff
==============================================================================
--- polly/trunk/lib/Analysis/ScopInfo.cpp (original)
+++ polly/trunk/lib/Analysis/ScopInfo.cpp Tue Nov 1 15:53:11 2016
@@ -816,10 +816,14 @@ void MemoryAccess::buildAccessRelation(c
isl_ctx *Ctx = isl_id_get_ctx(Id);
isl_id *BaseAddrId = SAI->getBasePtrId();
- if (!isAffine()) {
- if (isa<MemIntrinsic>(getAccessInstruction()))
- buildMemIntrinsicAccessRelation();
+ if (getAccessInstruction() && isa<MemIntrinsic>(getAccessInstruction())) {
+ buildMemIntrinsicAccessRelation();
+ AccessRelation =
+ isl_map_set_tuple_id(AccessRelation, isl_dim_out, BaseAddrId);
+ return;
+ }
+ if (!isAffine()) {
// We overapproximate non-affine accesses with a possible access to the
// whole array. For read accesses it does not make a difference, if an
// access must or may happen. However, for write accesses it is important to
Modified: polly/trunk/test/ScopInfo/aliasing_with_non_affine_access.ll
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/test/ScopInfo/aliasing_with_non_affine_access.ll?rev=285746&r1=285745&r2=285746&view=diff
==============================================================================
--- polly/trunk/test/ScopInfo/aliasing_with_non_affine_access.ll (original)
+++ polly/trunk/test/ScopInfo/aliasing_with_non_affine_access.ll Tue Nov 1 15:53:11 2016
@@ -1,18 +1,16 @@
-; RUN: opt %loadPolly -analyze -polly-scops < %s | FileCheck %s
-; RUN: opt %loadPolly -analyze -polly-scops -pass-remarks-analysis="polly-scops" 2>&1 < %s | FileCheck %s --check-prefix=REMARK
+; RUN: opt %loadPolly -analyze -polly-ast -polly-process-unprofitable -polly-allow-nonaffine < %s | FileCheck %s
;
-; This test case has a non-affine access (the memset call) that aliases with
-; other accesses. Thus, we bail out.
+; @test1
+; Make sure we generate the correct aliasing check for a fixed-size memset operation.
+; CHECK: if (1 && (&MemRef_0[15] <= &MemRef_1[0] || &MemRef_1[32] <= &MemRef_0[14]))
;
-; CHECK-NOT: Statements
+; @test2
+; Make sure we generate the correct aliasing check for a variable-size memset operation.
+; CHECK: if (1 && (&MemRef_0[15] <= &MemRef_1[0] || &MemRef_1[n] <= &MemRef_0[14]))
;
-; REMARK: remark: <unknown>:0:0: SCoP begins here.
-; REMARK-NEXT: remark: <unknown>:0:0: Possibly aliasing pointer, use restrict keyword.
-; REMARK-NEXT: remark: <unknown>:0:0: Possibly aliasing pointer, use restrict keyword.
-; REMARK-NEXT: remark: <unknown>:0:0: No-aliasing assumption: { : 1 = 0 }
-; REMARK-NEXT: remark: <unknown>:0:0: SCoP ends here but was dismissed.
+; @test3
+; We can't do anything interesting with a non-affine memset; just make sure it doesn't crash.
;
-; ModuleID = 'bugpoint-reduced-simplified.bc'
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
%struct.info = type { i32, %struct.ctr*, i32, %struct.ord*, %struct.ctr*, i32, i8*, i32, i32, double }
@@ -22,8 +20,7 @@ target datalayout = "e-m:e-i64:64-f80:12
; Function Attrs: argmemonly nounwind
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) #0
-; Function Attrs: nounwind uwtable
-define void @bestVirtualIndex(%struct.info** %ppIdxInfo) {
+define void @test1(%struct.info** %ppIdxInfo) {
entry:
%0 = load %struct.info*, %struct.info** %ppIdxInfo, align 8
br label %if.end125
@@ -46,4 +43,55 @@ if.end149:
unreachable
}
+define void @test2(%struct.info** %ppIdxInfo, i64 %n) {
+entry:
+ %0 = load %struct.info*, %struct.info** %ppIdxInfo, align 8
+ br label %if.end125
+
+if.end125: ; preds = %entry
+ %1 = load %struct.ctr*, %struct.ctr** undef, align 8
+ br label %for.end143
+
+for.end143: ; preds = %if.end125
+ %2 = bitcast %struct.ctr* %1 to i8*
+ tail call void @llvm.memset.p0i8.i64(i8* %2, i8 0, i64 %n, i32 4, i1 false)
+ %needToFreeIdxStr = getelementptr inbounds %struct.info, %struct.info* %0, i64 0, i32 7
+ %3 = load i32, i32* %needToFreeIdxStr, align 8
+ br i1 false, label %if.end149, label %if.then148
+
+if.then148: ; preds = %for.end143
+ br label %if.end149
+
+if.end149: ; preds = %if.then148, %for.end143
+ unreachable
+}
+
+define i32 @test3(i32* %x, i32 %n) {
+entry:
+ br label %entry.split
+
+entry.split: ; preds = %entry
+ %conv = sext i32 %n to i64
+ %cmp8 = icmp sgt i32 %n, 0
+ br i1 %cmp8, label %for.body.lr.ph, label %for.cond.cleanup
+
+for.body.lr.ph: ; preds = %entry.split
+ %0 = bitcast i32* %x to i8*
+ br label %for.body
+
+for.cond.cleanup: ; preds = %for.body, %entry.split
+ ret i32 0
+
+for.body: ; preds = %for.body, %for.body.lr.ph
+ %i.09 = phi i64 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
+ %mul = mul nsw i64 %i.09, %i.09
+ tail call void @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 %mul, i32 4, i1 false)
+ %add = add nuw nsw i64 %i.09, 1000
+ %arrayidx = getelementptr inbounds i32, i32* %x, i64 %add
+ store i32 5, i32* %arrayidx, align 4
+ %inc = add nuw nsw i64 %i.09, 1
+ %exitcond = icmp eq i64 %inc, %conv
+ br i1 %exitcond, label %for.cond.cleanup, label %for.body
+}
+
attributes #0 = { argmemonly nounwind }
More information about the llvm-commits
mailing list