[llvm] c80cf48 - [Attributor] AAReachability : use isPotentiallyReachable in isKnownReachable
Johannes Doerfert via llvm-commits
llvm-commits at lists.llvm.org
Sat Apr 4 17:22:45 PDT 2020
Author: Shinji Okumura
Date: 2020-04-04T19:16:17-05:00
New Revision: c80cf48801be54ee008730a9fad7dbccc963fc80
URL: https://github.com/llvm/llvm-project/commit/c80cf48801be54ee008730a9fad7dbccc963fc80
DIFF: https://github.com/llvm/llvm-project/commit/c80cf48801be54ee008730a9fad7dbccc963fc80.diff
LOG: [Attributor] AAReachability : use isPotentiallyReachable in isKnownReachable
`isKnownReachable` had only interface (always returns true).
Changed it to call `isPotentiallyReachable`.
This change enables deductions of other Abstract Attributes depending on
AAReachability to use reachability information obtained from CFG, and it
can make them stronger.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D76210
Added:
Modified:
llvm/include/llvm/Transforms/IPO/Attributor.h
llvm/test/Transforms/Attributor/heap_to_stack.ll
llvm/test/Transforms/Attributor/misc.ll
llvm/test/Transforms/Attributor/noalias.ll
Removed:
################################################################################
diff --git a/llvm/include/llvm/Transforms/IPO/Attributor.h b/llvm/include/llvm/Transforms/IPO/Attributor.h
index 1165c68a37e9..f150b5581f1b 100644
--- a/llvm/include/llvm/Transforms/IPO/Attributor.h
+++ b/llvm/include/llvm/Transforms/IPO/Attributor.h
@@ -102,6 +102,7 @@
#include "llvm/ADT/SetVector.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AssumeBundleQueries.h"
+#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/CGSCCPassManager.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/Analysis/InlineCost.h"
@@ -2106,14 +2107,14 @@ struct AAReachability : public StateWrapper<BooleanState, AbstractAttribute>,
/// determines (and caches) reachability.
bool isAssumedReachable(const Instruction *From,
const Instruction *To) const {
- return true;
+ return isPotentiallyReachable(From, To);
}
/// Returns true if 'From' instruction is known to reach, 'To' instruction.
/// Users should provide two positions they are interested in, and the class
/// determines (and caches) reachability.
bool isKnownReachable(const Instruction *From, const Instruction *To) const {
- return true;
+ return isPotentiallyReachable(From, To);
}
/// Return an IR position, see struct IRPosition.
diff --git a/llvm/test/Transforms/Attributor/heap_to_stack.ll b/llvm/test/Transforms/Attributor/heap_to_stack.ll
index 707aea7bfda8..3adbf3812f17 100644
--- a/llvm/test/Transforms/Attributor/heap_to_stack.ll
+++ b/llvm/test/Transforms/Attributor/heap_to_stack.ll
@@ -184,7 +184,7 @@ define void @test7() {
define void @test8() {
%1 = tail call noalias i8* @malloc(i64 4)
; CHECK: %1 = tail call noalias i8* @malloc(i64 4)
- ; CHECK-NEXT: @no_sync_func(i8* nocapture nofree %1)
+ ; CHECK-NEXT: @no_sync_func(i8* noalias nocapture nofree %1)
tail call void @no_sync_func(i8* %1)
%2 = bitcast i8* %1 to i32*
store i32 10, i32* %2
@@ -199,7 +199,7 @@ define void @test8() {
define void @test9() {
%1 = tail call noalias i8* @malloc(i64 4)
; CHECK: %1 = tail call noalias i8* @malloc(i64 4)
- ; CHECK-NEXT: @no_sync_func(i8* nocapture nofree %1)
+ ; CHECK-NEXT: @no_sync_func(i8* noalias nocapture nofree %1)
tail call void @no_sync_func(i8* %1)
%2 = bitcast i8* %1 to i32*
store i32 10, i32* %2
diff --git a/llvm/test/Transforms/Attributor/misc.ll b/llvm/test/Transforms/Attributor/misc.ll
index 2b79bdbee21f..b660300bcc20 100644
--- a/llvm/test/Transforms/Attributor/misc.ll
+++ b/llvm/test/Transforms/Attributor/misc.ll
@@ -9,7 +9,7 @@ define internal void @internal(void (i8*)* %fp) {
; CHECK-SAME: (void (i8*)* nonnull [[FP:%.*]])
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = alloca i32, align 4
-; CHECK-NEXT: call void @foo(i32* nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
+; CHECK-NEXT: call void @foo(i32* noalias nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
; CHECK-NEXT: call void [[FP]](i8* bitcast (void (i32*)* @foo to i8*))
; CHECK-NEXT: call void @callback1(void (i32*)* nonnull @foo)
; CHECK-NEXT: call void @callback2(void (i8*)* bitcast (void (i32*)* @foo to void (i8*)*))
@@ -22,7 +22,7 @@ define internal void @internal(void (i8*)* %fp) {
; DECL_CS-SAME: (void (i8*)* nonnull [[FP:%.*]])
; DECL_CS-NEXT: entry:
; DECL_CS-NEXT: [[A:%.*]] = alloca i32, align 4
-; DECL_CS-NEXT: call void @foo(i32* nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
+; DECL_CS-NEXT: call void @foo(i32* noalias nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
; DECL_CS-NEXT: call void [[FP]](i8* bitcast (void (i32*)* @foo to i8*))
; DECL_CS-NEXT: call void @callback1(void (i32*)* nonnull @foo)
; DECL_CS-NEXT: call void @callback2(void (i8*)* nonnull bitcast (void (i32*)* @foo to void (i8*)*))
@@ -49,7 +49,7 @@ define void @external(void (i8*)* %fp) {
; CHECK-SAME: (void (i8*)* [[FP:%.*]])
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = alloca i32, align 4
-; CHECK-NEXT: call void @foo(i32* nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
+; CHECK-NEXT: call void @foo(i32* noalias nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
; CHECK-NEXT: call void @callback1(void (i32*)* nonnull @foo)
; CHECK-NEXT: call void @callback2(void (i8*)* bitcast (void (i32*)* @foo to void (i8*)*))
; CHECK-NEXT: call void @callback2(void (i8*)* [[FP]])
@@ -63,7 +63,7 @@ define void @external(void (i8*)* %fp) {
; DECL_CS-SAME: (void (i8*)* [[FP:%.*]])
; DECL_CS-NEXT: entry:
; DECL_CS-NEXT: [[A:%.*]] = alloca i32, align 4
-; DECL_CS-NEXT: call void @foo(i32* nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
+; DECL_CS-NEXT: call void @foo(i32* noalias nocapture nofree nonnull writeonly align 4 dereferenceable(4) [[A]])
; DECL_CS-NEXT: call void @callback1(void (i32*)* nonnull @foo)
; DECL_CS-NEXT: call void @callback2(void (i8*)* nonnull bitcast (void (i32*)* @foo to void (i8*)*))
; DECL_CS-NEXT: call void @callback2(void (i8*)* [[FP]])
diff --git a/llvm/test/Transforms/Attributor/noalias.ll b/llvm/test/Transforms/Attributor/noalias.ll
index 358528546f9d..0b7856e01d9a 100644
--- a/llvm/test/Transforms/Attributor/noalias.ll
+++ b/llvm/test/Transforms/Attributor/noalias.ll
@@ -255,10 +255,8 @@ define void @test12_1() {
define void @test12_2(){
; CHECK-LABEL: @test12_2(
; CHECK-NEXT: [[A:%.*]] = tail call noalias i8* @malloc(i64 4)
-; FIXME: This should be @use_nocapture(i8* noalias [[A]])
-; CHECK-NEXT: tail call void @use_nocapture(i8* nocapture [[A]])
-; FIXME: This should be @use_nocapture(i8* noalias nocapture [[A]])
-; CHECK-NEXT: tail call void @use_nocapture(i8* nocapture [[A]])
+; CHECK-NEXT: tail call void @use_nocapture(i8* noalias nocapture [[A]])
+; CHECK-NEXT: tail call void @use_nocapture(i8* noalias nocapture [[A]])
; CHECK-NEXT: tail call void @use(i8* [[A]])
; CHECK-NEXT: tail call void @use_nocapture(i8* nocapture [[A]])
; CHECK-NEXT: ret void
@@ -393,3 +391,82 @@ declare dso_local double @__floatscan(%struct._IO_FILE*, i32, i32) local_unnamed
; Function Attrs: argmemonly nounwind willreturn
declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture)
+
+; Test 15
+; propagate noalias to some callsite arguments that there is no possibly reachable capture before it
+
+ at alias_of_p = external global i32*
+
+define void @make_alias(i32* %p) {
+ store i32* %p, i32** @alias_of_p
+ ret void
+}
+
+define void @only_store(i32* %p) {
+ store i32 0, i32* %p
+ ret void
+}
+
+; CHECK-LABEL define void @test15_caller(i32* noalias %p, i32 %c)
+define void @test15_caller(i32* noalias %p, i32 %c) {
+ %tobool = icmp eq i32 %c, 0
+ br i1 %tobool, label %if.end, label %if.then
+
+; CHECK tail call void @only_store(i32* noalias %p)
+; CHECK tail call void @make_alias(i32* %p)
+
+if.then:
+ tail call void @only_store(i32* %p)
+ br label %if.end
+
+if.end:
+ tail call void @make_alias(i32* %p)
+ ret void
+}
+
+; Test 16
+;
+; __attribute__((noinline)) static void test16_sub(int * restrict p, int c1, int c2) {
+; if (c1) {
+; only_store(p);
+; make_alias(p);
+; }
+; if (!c2) {
+; only_store(p);
+; }
+; }
+; void test16_caller(int * restrict p, int c) {
+; test16_sub(p, c, c);
+; }
+
+; CHECK-LABEL define internal void @test16_sub(i32* noalias %p, i32 %c1, i32 %c2)
+define internal void @test16_sub(i32* noalias %p, i32 %c1, i32 %c2) {
+ %tobool = icmp eq i32 %c1, 0
+ br i1 %tobool, label %if.end, label %if.then
+
+; CHECK tail call void @only_store(i32* noalias %p)
+if.then:
+ tail call void @only_store(i32* %p)
+ tail call void @make_alias(i32* %p)
+ br label %if.end
+if.end:
+
+ %tobool1 = icmp eq i32 %c2, 0
+ br i1 %tobool1, label %if.then2, label %if.end3
+
+; FIXME: this should be tail @only_store(i32* noalias %p)
+; when test16_caller is called, c1 always equals to c2. (Note that linkage is internal)
+; Therefore, only one of the two conditions of if statementes will be fulfilled.
+; CHECK tail call void @only_store(i32* %p)
+if.then2:
+ tail call void @only_store(i32* %p)
+ br label %if.end3
+if.end3:
+
+ ret void
+}
+
+define void @test16_caller(i32* %p, i32 %c) {
+ tail call void @test16_sub(i32* %p, i32 %c, i32 %c)
+ ret void
+}
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