shylie/llvm-project
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[Flang][AliasAnalysis] Alias analysis for tmp arrays (#111972)

Browse Source 
This patch extends the alias analysis for temporary arrays in Flang.
With this extension, Flang can now determine that the temporary array
[a, b, c] does not alias with arrayD in Fortran code:
```
  integer :: a, b, c
  integer :: arrayD(3)
  arrayD = [ a, b, c ]
```
This commit is contained in:
Dominik Adamski 2024-10-14 09:25:14 +02:00 committed by GitHub
parent 4722c6b87c
commit 102f76b2d7
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 52 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
flang/lib/Optimizer/Analysis/AliasAnalysis.cpp
View File

@ -257,6 +257,10 @@ AliasAnalysis::Source AliasAnalysis::getSource(mlir::Value v,
while (defOp && !breakFromLoop) {
ty = defOp->getResultTypes()[0];
llvm::TypeSwitch<Operation *>(defOp)
.Case<hlfir::AsExprOp>([&](auto op) {
v = op.getVar();
defOp = v.getDefiningOp();
})
.Case<fir::AllocaOp, fir::AllocMemOp>([&](auto op) {
// Unique memory allocation.
type = SourceKind::Allocate;

48
flang/test/Analysis/AliasAnalysis/alias-analysis-9.fir Normal file
View File

@ -0,0 +1,48 @@
// Use --mlir-disable-threading so that the AA queries are serialized
// as well as its diagnostic output.
// RUN: fir-opt %s -pass-pipeline='builtin.module(func.func(test-fir-alias-analysis))' -split-input-file --mlir-disable-threading 2>&1 | FileCheck %s
// Fortran source code:
// program TestTmpArrayAssignment
// integer :: a, b, c
// integer :: arrayD(3)
//
// arrayD = [ a, b, c ]
// end program TestTmpArrayAssignment
// CHECK-LABEL: Testing : "_QPTestTmpArrayAssignment"
// CHECK-DAG: ArrayD#0 <-> tmp_array#0: NoAlias
func.func @_QPTestTmpArrayAssignment() attributes {fir.bindc_name = "testtmparrayassignment"} {
%0 = fir.alloca i32 {bindc_name = "a", uniq_name = "_QFEa"}
%1:2 = hlfir.declare %0 {uniq_name = "_QFEa"} : (!fir.ref<i32>) -> (!fir.ref<i32>, !fir.ref<i32>)
%c3 = arith.constant 3 : index
%2 = fir.alloca !fir.array<3xi32> {bindc_name = "arrayd", uniq_name = "_QFEarrayd", test.ptr = "ArrayD" }
%3 = fir.shape %c3 : (index) -> !fir.shape<1>
%4:2 = hlfir.declare %2(%3) {uniq_name = "_QFEarrayd"} : (!fir.ref<!fir.array<3xi32>>, !fir.shape<1>) -> (!fir.ref<!fir.array<3xi32>>, !fir.ref<!fir.array<3xi32>>)
%5 = fir.alloca i32 {bindc_name = "b", uniq_name = "_QFEb"}
%6:2 = hlfir.declare %5 {uniq_name = "_QFEb"} : (!fir.ref<i32>) -> (!fir.ref<i32>, !fir.ref<i32>)
%7 = fir.alloca i32 {bindc_name = "c", uniq_name = "_QFEc"}
%8:2 = hlfir.declare %7 {uniq_name = "_QFEc"} : (!fir.ref<i32>) -> (!fir.ref<i32>, !fir.ref<i32>)
%c3_0 = arith.constant 3 : index
%c1 = arith.constant 1 : index
%c1_1 = arith.constant 1 : index
%9 = fir.allocmem !fir.array<3xi32> {bindc_name = ".tmp.arrayctor", uniq_name = ""}
%10 = fir.shape %c3_0 : (index) -> !fir.shape<1>
%11:2 = hlfir.declare %9(%10) {uniq_name = ".tmp.arrayctor"} : (!fir.heap<!fir.array<3xi32>>, !fir.shape<1>) -> (!fir.heap<!fir.array<3xi32>>, !fir.heap<!fir.array<3xi32>>)
%12 = fir.load %1#0 : !fir.ref<i32>
%13 = arith.addi %c1, %c1_1 : index
%14 = hlfir.designate %11#0 (%c1) : (!fir.heap<!fir.array<3xi32>>, index) -> !fir.ref<i32>
hlfir.assign %12 to %14 : i32, !fir.ref<i32>
%15 = fir.load %6#0 : !fir.ref<i32>
%16 = arith.addi %13, %c1_1 : index
%17 = hlfir.designate %11#0 (%13) : (!fir.heap<!fir.array<3xi32>>, index) -> !fir.ref<i32>
hlfir.assign %15 to %17 : i32, !fir.ref<i32>
%18 = fir.load %8#0 : !fir.ref<i32>
%19 = hlfir.designate %11#0 (%16) : (!fir.heap<!fir.array<3xi32>>, index) -> !fir.ref<i32>
hlfir.assign %18 to %19 : i32, !fir.ref<i32>
%true = arith.constant true
%20 = hlfir.as_expr %11#0 move %true {test.ptr = "tmp_array"}: (!fir.heap<!fir.array<3xi32>>, i1) -> !hlfir.expr<3xi32>
hlfir.assign %20 to %4#0 : !hlfir.expr<3xi32>, !fir.ref<!fir.array<3xi32>>
hlfir.destroy %20 : !hlfir.expr<3xi32>
return
}