r339832 - Implementation of nested loops in cxx_loop_proto
Emmett Neyman via cfe-commits
cfe-commits at lists.llvm.org
Wed Aug 15 16:05:48 PDT 2018
Author: emmettneyman
Date: Wed Aug 15 16:05:48 2018
New Revision: 339832
URL: http://llvm.org/viewvc/llvm-project?rev=339832&view=rev
Log:
Implementation of nested loops in cxx_loop_proto
Summary: Extended `cxx_loop_proto` to have neste for loops. Modified `loop_proto_to_llvm` and `loop_proto_to_cxx` to handle the new protos. All protos have a set of statements designated as "inner loop" statements and a set of statements designated as "outer loop" statements.
Reviewers: morehouse, kcc
Reviewed By: morehouse
Subscribers: cfe-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D50670
Modified:
cfe/trunk/tools/clang-fuzzer/cxx_loop_proto.proto
cfe/trunk/tools/clang-fuzzer/proto-to-cxx/loop_proto_to_cxx.cpp
cfe/trunk/tools/clang-fuzzer/proto-to-llvm/loop_proto_to_llvm.cpp
Modified: cfe/trunk/tools/clang-fuzzer/cxx_loop_proto.proto
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/tools/clang-fuzzer/cxx_loop_proto.proto?rev=339832&r1=339831&r2=339832&view=diff
==============================================================================
--- cfe/trunk/tools/clang-fuzzer/cxx_loop_proto.proto (original)
+++ cfe/trunk/tools/clang-fuzzer/cxx_loop_proto.proto Wed Aug 15 16:05:48 2018
@@ -9,10 +9,11 @@
///
/// \file
/// This file describes a subset of C++ as a protobuf. It is used to
-/// more easily find interesting inputs for fuzzing Clang. This subset
-/// differs from the one defined in cxx_proto.proto by eliminating while
-/// loops and conditionals. The goal is that the C++ code generated will be
-/// more likely to stress the LLVM loop vectorizer.
+/// more easily find interesting inputs for fuzzing LLVM's vectorizer.
+/// This subset differs from the one defined in cxx_proto.proto by eliminating
+/// while loops and conditionals. The goal is that the C++ code generated will
+/// be more likely to stress the LLVM loop vectorizer. The code generated will
+/// contain either a single loop or two nested loops.
///
//===----------------------------------------------------------------------===//
@@ -74,7 +75,8 @@ message StatementSeq {
}
message LoopFunction {
- required StatementSeq statements = 1;
+ optional StatementSeq inner_statements = 1;
+ required StatementSeq outer_statements = 2;
}
package clang_fuzzer;
Modified: cfe/trunk/tools/clang-fuzzer/proto-to-cxx/loop_proto_to_cxx.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/tools/clang-fuzzer/proto-to-cxx/loop_proto_to_cxx.cpp?rev=339832&r1=339831&r2=339832&view=diff
==============================================================================
--- cfe/trunk/tools/clang-fuzzer/proto-to-cxx/loop_proto_to_cxx.cpp (original)
+++ cfe/trunk/tools/clang-fuzzer/proto-to-cxx/loop_proto_to_cxx.cpp Wed Aug 15 16:05:48 2018
@@ -8,10 +8,10 @@
//===----------------------------------------------------------------------===//
//
// Implements functions for converting between protobufs and C++. Differs from
-// proto_to_cxx.cpp by wrapping all the generated C++ code in a single for
-// loop. Also coutputs a different function signature that includes a
-// size_t parameter for the loop to use. The C++ code generated is meant to
-// stress the LLVM loop vectorizer.
+// proto_to_cxx.cpp by wrapping all the generated C++ code in either a single
+// for loop or two nested loops. Also outputs a different function signature
+// that includes a size_t parameter for the loop to use. The C++ code generated
+// is meant to stress the LLVM loop vectorizer.
//
// Still a work in progress.
//
@@ -28,6 +28,17 @@
namespace clang_fuzzer {
+static bool inner_loop = false;
+class InnerLoop {
+ public:
+ InnerLoop() {
+ inner_loop = true;
+ }
+ ~InnerLoop() {
+ inner_loop = false;
+ }
+};
+
// Forward decls.
std::ostream &operator<<(std::ostream &os, const BinaryOp &x);
std::ostream &operator<<(std::ostream &os, const StatementSeq &x);
@@ -37,13 +48,14 @@ std::ostream &operator<<(std::ostream &o
return os << "(" << x.val() << ")";
}
std::ostream &operator<<(std::ostream &os, const VarRef &x) {
+ std::string which_loop = inner_loop ? "j" : "i";
switch (x.arr()) {
case VarRef::ARR_A:
- return os << "a[i]";
+ return os << "a[" << which_loop << "]";
case VarRef::ARR_B:
- return os << "b[i]";
+ return os << "b[" << which_loop << "]";
case VarRef::ARR_C:
- return os << "c[i]";
+ return os << "c[" << which_loop << "]";
}
}
std::ostream &operator<<(std::ostream &os, const Rvalue &x) {
@@ -108,10 +120,27 @@ std::ostream &operator<<(std::ostream &o
os << st;
return os;
}
+void NestedLoopToString(std::ostream &os, const LoopFunction &x) {
+ os << "void foo(int *a, int *b, int *__restrict__ c, size_t s) {\n"
+ << "for (int i=0; i<s; i++){\n"
+ << "for (int j=0; j<s; j++){\n";
+ {
+ InnerLoop IL;
+ os << x.inner_statements() << "}\n";
+ }
+ os << x.outer_statements() << "}\n}\n";
+}
+void SingleLoopToString(std::ostream &os, const LoopFunction &x) {
+ os << "void foo(int *a, int *b, int *__restrict__ c, size_t s) {\n"
+ << "for (int i=0; i<s; i++){\n"
+ << x.outer_statements() << "}\n}\n";
+}
std::ostream &operator<<(std::ostream &os, const LoopFunction &x) {
- return os << "void foo(int *a, int *b, int *__restrict__ c, size_t s) {\n"
- << "for (int i=0; i<s; i++){\n"
- << x.statements() << "}\n}\n";
+ if (x.has_inner_statements())
+ NestedLoopToString(os, x);
+ else
+ SingleLoopToString(os, x);
+ return os;
}
// ---------------------------------
Modified: cfe/trunk/tools/clang-fuzzer/proto-to-llvm/loop_proto_to_llvm.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/tools/clang-fuzzer/proto-to-llvm/loop_proto_to_llvm.cpp?rev=339832&r1=339831&r2=339832&view=diff
==============================================================================
--- cfe/trunk/tools/clang-fuzzer/proto-to-llvm/loop_proto_to_llvm.cpp (original)
+++ cfe/trunk/tools/clang-fuzzer/proto-to-llvm/loop_proto_to_llvm.cpp Wed Aug 15 16:05:48 2018
@@ -30,17 +30,30 @@ std::string BinopToString(std::ostream &
std::string StateSeqToString(std::ostream &os, const StatementSeq &x);
// Counter variable to generate new LLVM IR variable names and wrapper function
-std::string get_var() {
+static std::string get_var() {
static int ctr = 0;
return "%var" + std::to_string(ctr++);
}
+static bool inner_loop = false;
+class InnerLoop {
+ public:
+ InnerLoop() {
+ inner_loop = true;
+ }
+ ~InnerLoop() {
+ inner_loop = false;
+ }
+};
+
+
// Proto to LLVM.
std::string ConstToString(const Const &x) {
return std::to_string(x.val());
}
std::string VarRefToString(std::ostream &os, const VarRef &x) {
+ std::string which_loop = inner_loop ? "inner" : "outer";
std::string arr;
switch(x.arr()) {
case VarRef::ARR_A:
@@ -54,7 +67,8 @@ std::string VarRefToString(std::ostream
break;
}
std::string ptr_var = get_var();
- os << ptr_var << " = getelementptr inbounds i32, i32* " << arr << ", i64 %ct\n";
+ os << ptr_var << " = getelementptr inbounds i32, i32* " << arr
+ << ", i64 %" << which_loop << "_ct\n";
return ptr_var;
}
std::string RvalueToString(std::ostream &os, const Rvalue &x) {
@@ -122,25 +136,61 @@ std::ostream &operator<<(std::ostream &o
}
return os;
}
+void NestedLoopToString(std::ostream &os, const LoopFunction &x) {
+ os << "target triple = \"x86_64-unknown-linux-gnu\"\n"
+ << "define void @foo(i32* %a, i32* %b, i32* noalias %c, i64 %s) {\n"
+ << "outer_loop_start:\n"
+ << "%cmp = icmp sgt i64 %s, 0\n"
+ << "br i1 %cmp, label %inner_loop_start, label %end\n"
+ << "outer_loop:\n"
+ << x.outer_statements()
+ << "%o_ct_new = add i64 %outer_ct, 1\n"
+ << "%jmp_outer = icmp eq i64 %o_ct_new, %s\n"
+ << "br i1 %jmp_outer, label %end, label %inner_loop_start\n"
+ << "inner_loop_start:\n"
+ << "%outer_ct = phi i64 [%o_ct_new, %outer_loop], [0, %outer_loop_start]\n"
+ << "br label %inner_loop\n"
+ << "inner_loop:\n"
+ << "%inner_ct = phi i64 [0, %inner_loop_start], [%i_ct_new, %inner_loop]\n";
+ {
+ InnerLoop IL;
+ os << x.inner_statements();
+ }
+ os << "%i_ct_new = add i64 %inner_ct, 1\n"
+ << "%jmp_inner = icmp eq i64 %i_ct_new, %s\n"
+ << "br i1 %jmp_inner, label %outer_loop, label %inner_loop, !llvm.loop !0\n"
+ << "end:\n"
+ << "ret void\n"
+ << "}\n"
+ << "!0 = distinct !{!0, !1, !2}\n"
+ << "!1 = !{!\"llvm.loop.vectorize.enable\", i1 true}\n"
+ << "!2 = !{!\"llvm.loop.vectorize.width\", i32 " << kArraySize << "}\n";
+}
+void SingleLoopToString(std::ostream &os, const LoopFunction &x) {
+ os << "target triple = \"x86_64-unknown-linux-gnu\"\n"
+ << "define void @foo(i32* %a, i32* %b, i32* noalias %c, i64 %s) {\n"
+ << "%cmp = icmp sgt i64 %s, 0\n"
+ << "br i1 %cmp, label %start, label %end\n"
+ << "start:\n"
+ << "br label %loop\n"
+ << "end:\n"
+ << "ret void\n"
+ << "loop:\n"
+ << "%outer_ct = phi i64 [ %ctnew, %loop ], [ 0, %start ]\n"
+ << x.outer_statements()
+ << "%ctnew = add i64 %outer_ct, 1\n"
+ << "%j = icmp eq i64 %ctnew, %s\n"
+ << "br i1 %j, label %end, label %loop, !llvm.loop !0\n}\n"
+ << "!0 = distinct !{!0, !1, !2}\n"
+ << "!1 = !{!\"llvm.loop.vectorize.enable\", i1 true}\n"
+ << "!2 = !{!\"llvm.loop.vectorize.width\", i32 " << kArraySize << "}\n";
+}
std::ostream &operator<<(std::ostream &os, const LoopFunction &x) {
- return os << "target triple = \"x86_64-unknown-linux-gnu\"\n"
- << "define void @foo(i32* %a, i32* %b, i32* %c, i64 %s) {\n"
- << "%1 = icmp sgt i64 %s, 0\n"
- << "br i1 %1, label %start, label %end\n"
- << "start:\n"
- << "br label %loop\n"
- << "end:\n"
- << "ret void\n"
- << "loop:\n"
- << " %ct = phi i64 [ %ctnew, %loop ], [ 0, %start ]\n"
- << x.statements()
- << "%ctnew = add i64 %ct, 1\n"
- << "%j = icmp eq i64 %ctnew, %s\n"
- << "br i1 %j, label %end, label %loop, !llvm.loop !0\n}\n"
- << "!0 = distinct !{!0, !1, !2}\n"
- << "!1 = !{!\"llvm.loop.vectorize.enable\", i1 true}\n"
- << "!2 = !{!\"llvm.loop.vectorize.width\", i32 " << kArraySize
- << "}\n";
+ if (x.has_inner_statements())
+ NestedLoopToString(os, x);
+ else
+ SingleLoopToString(os, x);
+ return os;
}
// ---------------------------------
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