Fix for issue #512

backends/bmv2/midend.cpp

@@ -165,6 +165,7 @@ MidEnd::MidEnd(CompilerOptions& options) {
         new P4::SimplifySelectList(&refMap, &typeMap),
         new P4::RemoveSelectBooleans(&refMap, &typeMap),
         new P4::Predication(&refMap),
+        new P4::MoveDeclarations(),  // more may have been introduced
         new P4::ConstantFolding(&refMap, &typeMap),
         new P4::LocalCopyPropagation(&refMap, &typeMap),
         new P4::ConstantFolding(&refMap, &typeMap),

backends/p4test/midend.cpp

@@ -129,6 +129,7 @@ MidEnd::MidEnd(CompilerOptions& options) {
         new P4::SimplifySelectList(&refMap, &typeMap),
         new P4::RemoveSelectBooleans(&refMap, &typeMap),
         new P4::Predication(&refMap),
+        new P4::MoveDeclarations(),  // more may have been introduced
         new P4::ConstantFolding(&refMap, &typeMap),
         new P4::LocalCopyPropagation(&refMap, &typeMap),
         new P4::ConstantFolding(&refMap, &typeMap),

testdata/p4_16_samples/issue512.p4

@@ -0,0 +1,100 @@
+/*
+Copyright 2017 Cisco Systems, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#include <core.p4>
+#include <v1model.p4>
+
+typedef bit<48>  EthernetAddress;
+
+header Ethernet_h {
+    EthernetAddress dstAddr;
+    EthernetAddress srcAddr;
+    bit<16>         etherType;
+}
+
+struct Parsed_packet {
+    Ethernet_h    ethernet;
+}
+
+struct mystruct1 {
+    bit<4>  a;
+    bit<4>  b;
+}
+
+control DeparserI(packet_out packet,
+                  in Parsed_packet hdr) {
+    apply { packet.emit(hdr.ethernet); }
+}
+
+parser parserI(packet_in pkt,
+               out Parsed_packet hdr,
+               inout mystruct1 meta,
+               inout standard_metadata_t stdmeta) {
+    state start {
+        pkt.extract(hdr.ethernet);
+        transition accept;
+    }
+}
+
+control cIngress(inout Parsed_packet hdr,
+                 inout mystruct1 meta,
+                 inout standard_metadata_t stdmeta) {
+    action foo() {
+        meta.b = meta.b + 5;
+        if (meta.b > 10) {
+            // As written, this code gives p4test error "Could not
+            // find declaration for pred"
+
+            // Commmenting out any one of line (a) or (b) or (c)
+            // causes error to go away.
+            meta.b = meta.b ^ 5;   // line (a)
+            return;                // line (b)
+        }
+        meta.b = meta.b + 5;       // line (c)
+    }
+    table guh {
+        key = { hdr.ethernet.srcAddr : exact; }
+        actions = { foo; }
+        default_action = foo;
+    }
+
+    apply {
+        guh.apply();
+    }
+}
+
+control cEgress(inout Parsed_packet hdr,
+                inout mystruct1 meta,
+                inout standard_metadata_t stdmeta) {
+    apply { }
+}
+
+control vc(in Parsed_packet hdr,
+           inout mystruct1 meta) {
+    apply { }
+}
+
+control uc(inout Parsed_packet hdr,
+           inout mystruct1 meta) {
+    apply { }
+}
+
+V1Switch<Parsed_packet, mystruct1>(parserI(),
+                                   vc(),
+                                   cIngress(),
+                                   cEgress(),
+                                   uc(),
+                                   DeparserI()) main;

testdata/p4_16_samples_outputs/issue512-frontend.p4

@@ -0,0 +1,71 @@
+#include <core.p4>
+#include <v1model.p4>
+
+typedef bit<48> EthernetAddress;
+header Ethernet_h {
+    EthernetAddress dstAddr;
+    EthernetAddress srcAddr;
+    bit<16>         etherType;
+}
+
+struct Parsed_packet {
+    Ethernet_h ethernet;
+}
+
+struct mystruct1 {
+    bit<4> a;
+    bit<4> b;
+}
+
+control DeparserI(packet_out packet, in Parsed_packet hdr) {
+    apply {
+        packet.emit<Ethernet_h>(hdr.ethernet);
+    }
+}
+
+parser parserI(packet_in pkt, out Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    state start {
+        pkt.extract<Ethernet_h>(hdr.ethernet);
+        transition accept;
+    }
+}
+
+control cIngress(inout Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    @name("foo") action foo_0() {
+        meta.b = meta.b + 4w5;
+        if (meta.b > 4w10) {
+            meta.b = meta.b ^ 4w5;
+            return;
+        }
+        meta.b = meta.b + 4w5;
+    }
+    @name("guh") table guh_0 {
+        key = {
+            hdr.ethernet.srcAddr: exact @name("hdr.ethernet.srcAddr") ;
+        }
+        actions = {
+            foo_0();
+        }
+        default_action = foo_0();
+    }
+    apply {
+        guh_0.apply();
+    }
+}
+
+control cEgress(inout Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    apply {
+    }
+}
+
+control vc(in Parsed_packet hdr, inout mystruct1 meta) {
+    apply {
+    }
+}
+
+control uc(inout Parsed_packet hdr, inout mystruct1 meta) {
+    apply {
+    }
+}
+
+V1Switch<Parsed_packet, mystruct1>(parserI(), vc(), cIngress(), cEgress(), uc(), DeparserI()) main;

testdata/p4_16_samples_outputs/issue512-midend.p4

@@ -0,0 +1,70 @@
+#include <core.p4>
+#include <v1model.p4>
+
+typedef bit<48> EthernetAddress;
+header Ethernet_h {
+    EthernetAddress dstAddr;
+    EthernetAddress srcAddr;
+    bit<16>         etherType;
+}
+
+struct Parsed_packet {
+    Ethernet_h ethernet;
+}
+
+struct mystruct1 {
+    bit<4> a;
+    bit<4> b;
+}
+
+control DeparserI(packet_out packet, in Parsed_packet hdr) {
+    apply {
+        packet.emit<Ethernet_h>(hdr.ethernet);
+    }
+}
+
+parser parserI(packet_in pkt, out Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    state start {
+        pkt.extract<Ethernet_h>(hdr.ethernet);
+        transition accept;
+    }
+}
+
+control cIngress(inout Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    bool pred;
+    @name("foo") action foo_0() {
+        meta.b = meta.b + 4w5;
+        pred = meta.b > 4w10;
+        meta.b = (meta.b > 4w10 ? meta.b ^ 4w5 : meta.b);
+        meta.b = (!(pred ? true : false) ? meta.b + 4w5 : meta.b);
+    }
+    @name("guh") table guh {
+        key = {
+            hdr.ethernet.srcAddr: exact @name("hdr.ethernet.srcAddr") ;
+        }
+        actions = {
+            foo_0();
+        }
+        default_action = foo_0();
+    }
+    apply {
+        guh.apply();
+    }
+}
+
+control cEgress(inout Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    apply {
+    }
+}
+
+control vc(in Parsed_packet hdr, inout mystruct1 meta) {
+    apply {
+    }
+}
+
+control uc(inout Parsed_packet hdr, inout mystruct1 meta) {
+    apply {
+    }
+}
+
+V1Switch<Parsed_packet, mystruct1>(parserI(), vc(), cIngress(), cEgress(), uc(), DeparserI()) main;

testdata/p4_16_samples_outputs/issue512.p4

@@ -0,0 +1,71 @@
+#include <core.p4>
+#include <v1model.p4>
+
+typedef bit<48> EthernetAddress;
+header Ethernet_h {
+    EthernetAddress dstAddr;
+    EthernetAddress srcAddr;
+    bit<16>         etherType;
+}
+
+struct Parsed_packet {
+    Ethernet_h ethernet;
+}
+
+struct mystruct1 {
+    bit<4> a;
+    bit<4> b;
+}
+
+control DeparserI(packet_out packet, in Parsed_packet hdr) {
+    apply {
+        packet.emit(hdr.ethernet);
+    }
+}
+
+parser parserI(packet_in pkt, out Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    state start {
+        pkt.extract(hdr.ethernet);
+        transition accept;
+    }
+}
+
+control cIngress(inout Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    action foo() {
+        meta.b = meta.b + 5;
+        if (meta.b > 10) {
+            meta.b = meta.b ^ 5;
+            return;
+        }
+        meta.b = meta.b + 5;
+    }
+    table guh {
+        key = {
+            hdr.ethernet.srcAddr: exact;
+        }
+        actions = {
+            foo;
+        }
+        default_action = foo;
+    }
+    apply {
+        guh.apply();
+    }
+}
+
+control cEgress(inout Parsed_packet hdr, inout mystruct1 meta, inout standard_metadata_t stdmeta) {
+    apply {
+    }
+}
+
+control vc(in Parsed_packet hdr, inout mystruct1 meta) {
+    apply {
+    }
+}
+
+control uc(inout Parsed_packet hdr, inout mystruct1 meta) {
+    apply {
+    }
+}
+
+V1Switch<Parsed_packet, mystruct1>(parserI(), vc(), cIngress(), cEgress(), uc(), DeparserI()) main;