[Simplify] Mark (and sweep) based on latest access relation.

Previously we marked scalars based on the original access function. However,
when a scalar read access is redirected, the original definition
(or incoming values of a PHI) is not used anymore, and can be deleted
(unless referenced by use that has not been redirected).

llvm-svn: 316660

diff --git a/polly/lib/Support/VirtualInstruction.cpp b/polly/lib/Support/VirtualInstruction.cpp
index d30a27fd2d5845f1270c831e3f8c3c1ba21e0fa8..0e4718864896d585a3b0f2a66df07a47a1f620b5 100644 (file)
--- a/polly/lib/Support/VirtualInstruction.cpp
+++ b/polly/lib/Support/VirtualInstruction.cpp
@@ -311,7 +311,7 @@ static void walkReachable(Scop *S, LoopInfo *LI,
       if (Acc->isRead()) {
         const ScopArrayInfo *SAI = Acc->getScopArrayInfo();
 
-        if (Acc->isOriginalValueKind()) {
+        if (Acc->isLatestValueKind()) {
           MemoryAccess *DefAcc = S->getValueDef(SAI);
 
           // Accesses to read-only values do not have a definition.
@@ -319,7 +319,7 @@ static void walkReachable(Scop *S, LoopInfo *LI,
             WorklistAccs.push_back(S->getValueDef(SAI));
         }
 
-        if (Acc->isOriginalAnyPHIKind()) {
+        if (Acc->isLatestAnyPHIKind()) {
           auto IncomingMAs = S->getPHIIncomings(SAI);
           WorklistAccs.append(IncomingMAs.begin(), IncomingMAs.end());
         }

diff --git a/polly/test/Simplify/sweep_mapped_phi.ll b/polly/test/Simplify/sweep_mapped_phi.ll
new file mode 100644 (file)
index 0000000..4491d43
--- /dev/null
+++ b/polly/test/Simplify/sweep_mapped_phi.ll
@@ -0,0 +1,62 @@
+; RUN: opt %loadPolly -polly-import-jscop -polly-import-jscop-postfix=transformed -polly-simplify -analyze < %s | FileCheck %s -match-full-lines
+;
+; Map %phi to A[j], so the scalar write in Stmt_for_bodyA can be removed.
+;
+; for (int j = 0; j < n; j += 1) {
+; bodyA:
+;   val = 21.0 + 21.0;
+;   A[j] = val;
+;
+; bodyB:
+;   B[j] = val;
+; }
+;
+
+define void @sweep_mapped_phi(i32 %n, double* noalias nonnull %A, double* noalias nonnull %B) {
+entry:
+  br label %for
+
+for:
+  %j = phi i32 [0, %entry], [%j.inc, %inc]
+  %j.cmp = icmp slt i32 %j, %n
+  br i1 %j.cmp, label %bodyA, label %exit
+
+    bodyA:
+      %val = fadd double 21.0, 21.0
+      %A_idx = getelementptr inbounds double, double* %A, i32 %j
+      store double %val, double* %A_idx
+      br label %bodyB
+
+    bodyB:
+      %phi = phi double [%val, %bodyA]
+      %B_idx = getelementptr inbounds double, double* %B, i32 %j
+      store double %phi, double* %B_idx
+      br label %inc
+
+inc:
+  %j.inc = add nuw nsw i32 %j, 1
+  br label %for
+
+exit:
+  br label %return
+
+return:
+  ret void
+}
+
+
+; CHECK: Statistics {
+; CHECK:     Dead accesses removed: 1
+; CHECK: }
+
+; CHECK:      After accesses {
+; CHECK-NEXT:     Stmt_bodyA
+; CHECK-NEXT:             MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] };
+; CHECK-NEXT:     Stmt_bodyB
+; CHECK-NEXT:             ReadAccess :=       [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyB[i0] -> MemRef_phi__phi[] };
+; CHECK-NEXT:            new: [n] -> { Stmt_bodyB[i0] -> MemRef_A[i0] };
+; CHECK-NEXT:             MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] };
+; CHECK-NEXT: }

diff --git a/polly/test/Simplify/sweep_mapped_phi___%for---%return.jscop b/polly/test/Simplify/sweep_mapped_phi___%for---%return.jscop
new file mode 100644 (file)
index 0000000..0d2e0dd
--- /dev/null
+++ b/polly/test/Simplify/sweep_mapped_phi___%for---%return.jscop
@@ -0,0 +1,48 @@
+{
+   "arrays" : [
+      {
+         "name" : "MemRef_A",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      },
+      {
+         "name" : "MemRef_B",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      }
+   ],
+   "context" : "[n] -> {  : -2147483648 <= n <= 2147483647 }",
+   "name" : "%for---%return",
+   "statements" : [
+      {
+         "accesses" : [
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] }"
+            },
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_phi__phi[] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyA[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyA",
+         "schedule" : "[n] -> { Stmt_bodyA[i0] -> [i0, 0] }"
+      },
+      {
+         "accesses" : [
+            {
+               "kind" : "read",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_phi__phi[] }"
+            },
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyB[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyB",
+         "schedule" : "[n] -> { Stmt_bodyB[i0] -> [i0, 1] }"
+      }
+   ]
+}

diff --git a/polly/test/Simplify/sweep_mapped_phi___%for---%return.jscop.transformed b/polly/test/Simplify/sweep_mapped_phi___%for---%return.jscop.transformed
new file mode 100644 (file)
index 0000000..6ebc74c
--- /dev/null
+++ b/polly/test/Simplify/sweep_mapped_phi___%for---%return.jscop.transformed
@@ -0,0 +1,65 @@
+{
+   "arrays" : [
+      {
+         "name" : "MemRef_A",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      },
+      {
+         "name" : "MemRef_B",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      }
+   ],
+   "context" : "[n] -> {  : -2147483648 <= n <= 2147483647 }",
+   "name" : "%for---%return",
+   "statements" : [
+      {
+         "accesses" : [
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] }"
+            },
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_phi__phi[] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyA[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyA",
+         "schedule" : "[n] -> { Stmt_bodyA[i0] -> [i0, 0] }"
+      },
+      {
+         "accesses" : [
+            {
+               "kind" : "read",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_A[i0] }"
+            },
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyB[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyB",
+         "schedule" : "[n] -> { Stmt_bodyB[i0] -> [i0, 1] }"
+      }
+   ]
+}
+
+
+; CHECK: Statistics {
+; CHECK:     Dead accesses removed: 1
+; CHECK: }
+
+; CHECK:      After accesses {
+; CHECK-NEXT:     Stmt_bodyA
+; CHECK-NEXT:             MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] };
+; CHECK-NEXT:     Stmt_bodyB
+; CHECK-NEXT:             ReadAccess :=       [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyB[i0] -> MemRef_phi__phi[] };
+; CHECK-NEXT:            new: [n] -> { Stmt_bodyB[i0] -> MemRef_A[i0] };
+; CHECK-NEXT:             MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] };
+; CHECK-NEXT: }

diff --git a/polly/test/Simplify/sweep_mapped_value.ll b/polly/test/Simplify/sweep_mapped_value.ll
new file mode 100644 (file)
index 0000000..f193cf8
--- /dev/null
+++ b/polly/test/Simplify/sweep_mapped_value.ll
@@ -0,0 +1,61 @@
+; RUN: opt %loadPolly -polly-import-jscop -polly-import-jscop-postfix=transformed -polly-simplify -analyze < %s | FileCheck %s -match-full-lines
+;
+; Map %val to A[j], so the scalar write on Stmt_for_bodyB can be removed.
+;
+; for (int j = 0; j < n; j += 1) {
+; bodyA:
+;   double val = 21.0 + 21.0;
+;   A[j] = val;
+;
+; bodyB:
+;   B[j] = val;
+; }
+;
+
+define void @sweep_mapped_value(i32 %n, double* noalias nonnull %A, double* noalias nonnull %B) {
+entry:
+  br label %for
+
+for:
+  %j = phi i32 [0, %entry], [%j.inc, %inc]
+  %j.cmp = icmp slt i32 %j, %n
+  br i1 %j.cmp, label %bodyA, label %exit
+
+    bodyA:
+      %val = fadd double 21.0, 21.0
+      %A_idx = getelementptr inbounds double, double* %A, i32 %j
+      store double %val, double* %A_idx
+      br label %bodyB
+
+    bodyB:
+      %B_idx = getelementptr inbounds double, double* %B, i32 %j
+      store double %val, double* %B_idx
+      br label %inc
+
+inc:
+  %j.inc = add nuw nsw i32 %j, 1
+  br label %for
+
+exit:
+  br label %return
+
+return:
+  ret void
+}
+
+
+; CHECK: Statistics {
+; CHECK:     Dead accesses removed: 1
+; CHECK: }
+
+; CHECK:      After accesses {
+; CHECK-NEXT:     Stmt_bodyA
+; CHECK-NEXT:             MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] };
+; CHECK-NEXT:     Stmt_bodyB
+; CHECK-NEXT:             MustWriteAccess :=  [Reduction Type: NONE] [Scalar: 0]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] };
+; CHECK-NEXT:             ReadAccess :=       [Reduction Type: NONE] [Scalar: 1]
+; CHECK-NEXT:                 [n] -> { Stmt_bodyB[i0] -> MemRef_val[] };
+; CHECK-NEXT:            new: [n] -> { Stmt_bodyB[i0] -> MemRef_A[i0] };
+; CHECK-NEXT: }

diff --git a/polly/test/Simplify/sweep_mapped_value___%for---%return.jscop b/polly/test/Simplify/sweep_mapped_value___%for---%return.jscop
new file mode 100644 (file)
index 0000000..9a827f3
--- /dev/null
+++ b/polly/test/Simplify/sweep_mapped_value___%for---%return.jscop
@@ -0,0 +1,48 @@
+{
+   "arrays" : [
+      {
+         "name" : "MemRef_A",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      },
+      {
+         "name" : "MemRef_B",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      }
+   ],
+   "context" : "[n] -> {  : -2147483648 <= n <= 2147483647 }",
+   "name" : "%for---%return",
+   "statements" : [
+      {
+         "accesses" : [
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] }"
+            },
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_val[] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyA[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyA",
+         "schedule" : "[n] -> { Stmt_bodyA[i0] -> [i0, 0] }"
+      },
+      {
+         "accesses" : [
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] }"
+            },
+            {
+               "kind" : "read",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_val[] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyB[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyB",
+         "schedule" : "[n] -> { Stmt_bodyB[i0] -> [i0, 1] }"
+      }
+   ]
+}

diff --git a/polly/test/Simplify/sweep_mapped_value___%for---%return.jscop.transformed b/polly/test/Simplify/sweep_mapped_value___%for---%return.jscop.transformed
new file mode 100644 (file)
index 0000000..f790262
--- /dev/null
+++ b/polly/test/Simplify/sweep_mapped_value___%for---%return.jscop.transformed
@@ -0,0 +1,48 @@
+{
+   "arrays" : [
+      {
+         "name" : "MemRef_A",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      },
+      {
+         "name" : "MemRef_B",
+         "sizes" : [ "*" ],
+         "type" : "double"
+      }
+   ],
+   "context" : "[n] -> {  : -2147483648 <= n <= 2147483647 }",
+   "name" : "%for---%return",
+   "statements" : [
+      {
+         "accesses" : [
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_A[i0] }"
+            },
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyA[i0] -> MemRef_val[] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyA[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyA",
+         "schedule" : "[n] -> { Stmt_bodyA[i0] -> [i0, 0] }"
+      },
+      {
+         "accesses" : [
+            {
+               "kind" : "write",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_B[i0] }"
+            },
+            {
+               "kind" : "read",
+               "relation" : "[n] -> { Stmt_bodyB[i0] -> MemRef_A[i0] }"
+            }
+         ],
+         "domain" : "[n] -> { Stmt_bodyB[i0] : 0 <= i0 < n }",
+         "name" : "Stmt_bodyB",
+         "schedule" : "[n] -> { Stmt_bodyB[i0] -> [i0, 1] }"
+      }
+   ]
+}