[OpenMP][NVPTX][CUDA] Adding support for printf for an NVPTX OpenMP device.

Support for CUDA printf is exploited to support printf for
an NVPTX OpenMP device.

To reflect the support of both programming models, the file
CGCUDABuiltin.cpp has been renamed to CGGPUBuiltin.cpp, and
the call EmitCUDADevicePrintfCallExpr has been renamed to
EmitGPUDevicePrintfCallExpr.

Reviewers: jlebar
Differential Revision: https://reviews.llvm.org/D17890

llvm-svn: 293444

5 files changed, 127 insertions, 12 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index b1feefe9f0d..c70a447303f 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -2620,8 +2620,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
         Arg));
   }
   case Builtin::BIprintf:
-    if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice)
-      return EmitCUDADevicePrintfCallExpr(E, ReturnValue);
+    if (getTarget().getTriple().isNVPTX())
+      return EmitNVPTXDevicePrintfCallExpr(E, ReturnValue);
     break;
   case Builtin::BI__builtin_canonicalize:
   case Builtin::BI__builtin_canonicalizef:
diff --git a/clang/lib/CodeGen/CGCUDABuiltin.cpp b/clang/lib/CodeGen/CGGPUBuiltin.cpp
index 44dd003757a..48156b1b26b 100644
--- a/clang/lib/CodeGen/CGCUDABuiltin.cpp
+++ b/clang/lib/CodeGen/CGGPUBuiltin.cpp
@@ -1,4 +1,4 @@
-//===----- CGCUDABuiltin.cpp - Codegen for CUDA builtins ------------------===//
+//===------ CGGPUBuiltin.cpp - Codegen for GPU builtins -------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -7,8 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// Generates code for built-in CUDA calls which are not runtime-specific.
-// (Runtime-specific codegen lives in CGCUDARuntime.)
+// Generates code for built-in GPU calls which are not runtime-specific.
+// (Runtime-specific codegen lives in programming model specific files.)
 //
 //===----------------------------------------------------------------------===//
 
@@ -67,10 +67,9 @@ static llvm::Function *GetVprintfDeclaration(llvm::Module &M) {
 // Note that by the time this function runs, E's args have already undergone the
 // standard C vararg promotion (short -> int, float -> double, etc.).
 RValue
-CodeGenFunction::EmitCUDADevicePrintfCallExpr(const CallExpr *E,
-                                              ReturnValueSlot ReturnValue) {
-  assert(getLangOpts().CUDA);
-  assert(getLangOpts().CUDAIsDevice);
+CodeGenFunction::EmitNVPTXDevicePrintfCallExpr(const CallExpr *E,
+                                               ReturnValueSlot ReturnValue) {
+  assert(getTarget().getTriple().isNVPTX());
   assert(E->getBuiltinCallee() == Builtin::BIprintf);
   assert(E->getNumArgs() >= 1); // printf always has at least one arg.
 
diff --git a/clang/lib/CodeGen/CMakeLists.txt b/clang/lib/CodeGen/CMakeLists.txt
index 4fbf9f22a98..1e9a43af522 100644
--- a/clang/lib/CodeGen/CMakeLists.txt
+++ b/clang/lib/CodeGen/CMakeLists.txt
@@ -36,7 +36,6 @@ add_clang_library(clangCodeGen
   CGAtomic.cpp
   CGBlocks.cpp
   CGBuiltin.cpp
-  CGCUDABuiltin.cpp
   CGCUDANV.cpp
   CGCUDARuntime.cpp
   CGCXX.cpp
@@ -55,6 +54,7 @@ add_clang_library(clangCodeGen
   CGExprComplex.cpp
   CGExprConstant.cpp
   CGExprScalar.cpp
+  CGGPUBuiltin.cpp
   CGLoopInfo.cpp
   CGObjC.cpp
   CGObjCGNU.cpp
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 8d7fd3f80ba..098767e23e7 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -3106,8 +3106,8 @@ public:
   RValue EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
                                 ReturnValueSlot ReturnValue);
 
-  RValue EmitCUDADevicePrintfCallExpr(const CallExpr *E,
-                                      ReturnValueSlot ReturnValue);
+  RValue EmitNVPTXDevicePrintfCallExpr(const CallExpr *E,
+                                       ReturnValueSlot ReturnValue);
 
   RValue EmitBuiltinExpr(const FunctionDecl *FD,
                          unsigned BuiltinID, const CallExpr *E,
diff --git a/clang/test/OpenMP/nvptx_target_printf_codegen.c b/clang/test/OpenMP/nvptx_target_printf_codegen.c
new file mode 100644
index 00000000000..0de6885a5a7
--- /dev/null
+++ b/clang/test/OpenMP/nvptx_target_printf_codegen.c
@@ -0,0 +1,116 @@
+// Test target codegen - host bc file has to be created first.
+// RUN: %clang_cc1 -verify -fopenmp -x c -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc
+// RUN: %clang_cc1 -verify -fopenmp -x c -triple nvptx64-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-64
+// RUN: %clang_cc1 -verify -fopenmp -x c -triple i386-unknown-unknown -fopenmp-targets=nvptx-nvidia-cuda -emit-llvm-bc %s -o %t-x86-host.bc
+// RUN: %clang_cc1 -verify -fopenmp -x c -triple nvptx-unknown-unknown -fopenmp-targets=nvptx-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-x86-host.bc -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-32
+
+#include <stdarg.h>
+
+// expected-no-diagnostics
+extern int printf(const char *, ...);
+extern int vprintf(const char *, va_list);
+
+// Check a simple call to printf end-to-end.
+// CHECK: [[SIMPLE_PRINTF_TY:%[a-zA-Z0-9_]+]] = type { i32, i64, double }
+int CheckSimple() {
+    // CHECK: define {{.*}}void [[T1:@__omp_offloading_.+CheckSimple.+]]_worker()
+#pragma omp target
+  {
+    // Entry point.
+    // CHECK: define {{.*}}void [[T1]]()
+    // Alloca in entry block.
+    // CHECK: [[BUF:%[a-zA-Z0-9_]+]] = alloca [[SIMPLE_PRINTF_TY]]
+
+    // CHECK: {{call|invoke}} void [[T1]]_worker()
+    // CHECK: br label {{%?}}[[EXIT:.+]]
+    //
+    // CHECK-DAG: [[CMTID:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.tid.x()
+    // CHECK-DAG: [[CMNTH:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.ntid.x()
+    // CHECK-DAG: [[CMWS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+    // CHECK: [[IS_MASTER:%.+]] = icmp eq i32 [[CMTID]],
+    // CHECK: br i1 [[IS_MASTER]], label {{%?}}[[MASTER:.+]], label {{%?}}[[EXIT]]
+    //
+    // CHECK: [[MASTER]]
+    // CHECK-DAG: [[MNTH:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.ntid.x()
+    // CHECK-DAG: [[MWS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+    // CHECK: [[MTMP1:%.+]] = sub i32 [[MNTH]], [[MWS]]
+    // CHECK: call void @__kmpc_kernel_init(i32 [[MTMP1]]
+
+    // printf in master-only basic block.
+    // CHECK: [[FMT:%[0-9]+]] = load{{.*}}%fmt
+    const char* fmt = "%d %lld %f";
+    // CHECK: [[PTR0:%[0-9]+]] = getelementptr inbounds [[SIMPLE_PRINTF_TY]], [[SIMPLE_PRINTF_TY]]* [[BUF]], i32 0, i32 0
+    // CHECK: store i32 1, i32* [[PTR0]], align 4
+    // CHECK: [[PTR1:%[0-9]+]] = getelementptr inbounds [[SIMPLE_PRINTF_TY]], [[SIMPLE_PRINTF_TY]]* [[BUF]], i32 0, i32 1
+    // CHECK: store i64 2, i64* [[PTR1]], align 8
+    // CHECK: [[PTR2:%[0-9]+]] = getelementptr inbounds [[SIMPLE_PRINTF_TY]], [[SIMPLE_PRINTF_TY]]* [[BUF]], i32 0, i32 2
+
+    // CHECK: store double 3.0{{[^,]*}}, double* [[PTR2]], align 8
+    // CHECK: [[BUF_CAST:%[0-9]+]] = bitcast [[SIMPLE_PRINTF_TY]]* [[BUF]] to i8*
+    // CHECK: [[RET:%[0-9]+]] = call i32 @vprintf(i8* [[FMT]], i8* [[BUF_CAST]])
+    printf(fmt, 1, 2ll, 3.0);
+  }
+
+  return 0;
+}
+
+void CheckNoArgs() {
+    // CHECK: define {{.*}}void [[T2:@__omp_offloading_.+CheckNoArgs.+]]_worker()
+#pragma omp target
+  {
+    // Entry point.
+    // CHECK: define {{.*}}void [[T2]]()
+
+    // CHECK: {{call|invoke}} void [[T2]]_worker()
+    // CHECK: br label {{%?}}[[EXIT:.+]]
+    //
+    // CHECK-DAG: [[CMTID:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.tid.x()
+    // CHECK-DAG: [[CMNTH:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.ntid.x()
+    // CHECK-DAG: [[CMWS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+    // CHECK: [[IS_MASTER:%.+]] = icmp eq i32 [[CMTID]],
+    // CHECK: br i1 [[IS_MASTER]], label {{%?}}[[MASTER:.+]], label {{%?}}[[EXIT]]
+    //
+    // CHECK: [[MASTER]]
+    // CHECK-DAG: [[MNTH:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.ntid.x()
+    // CHECK-DAG: [[MWS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+    // CHECK: [[MTMP1:%.+]] = sub i32 [[MNTH]], [[MWS]]
+    // CHECK: call void @__kmpc_kernel_init(i32 [[MTMP1]]
+
+    // printf in master-only basic block.
+    // CHECK: call i32 @vprintf({{.*}}, i8* null){{$}}
+    printf("hello, world!");
+  }
+}
+
+// Check that printf's alloca happens in the entry block, not inside the if
+// statement.
+int foo;
+void CheckAllocaIsInEntryBlock() {
+    // CHECK: define {{.*}}void [[T3:@__omp_offloading_.+CheckAllocaIsInEntryBlock.+]]_worker()
+#pragma omp target
+  {
+    // Entry point.
+    // CHECK: define {{.*}}void [[T3]](
+    // Alloca in entry block.
+    // CHECK: alloca %printf_args
+
+    // CHECK: {{call|invoke}} void [[T3]]_worker()
+    // CHECK: br label {{%?}}[[EXIT:.+]]
+    //
+    // CHECK-DAG: [[CMTID:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.tid.x()
+    // CHECK-DAG: [[CMNTH:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.ntid.x()
+    // CHECK-DAG: [[CMWS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+    // CHECK: [[IS_MASTER:%.+]] = icmp eq i32 [[CMTID]],
+    // CHECK: br i1 [[IS_MASTER]], label {{%?}}[[MASTER:.+]], label {{%?}}[[EXIT]]
+    //
+    // CHECK: [[MASTER]]
+    // CHECK-DAG: [[MNTH:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.ntid.x()
+    // CHECK-DAG: [[MWS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+    // CHECK: [[MTMP1:%.+]] = sub i32 [[MNTH]], [[MWS]]
+    // CHECK: call void @__kmpc_kernel_init(i32 [[MTMP1]]
+
+    if (foo) {
+      printf("%d", 42);
+    }
+  }
+}