Annotate imprecise FP division with fpaccuracy metadata

The OpenCL single precision division operation is only required to
be accurate to 2.5ulp.  Annotate the fdiv instruction with metadata
which signals to the backend that an imprecise divide instruction
may be used.

llvm-svn: 143136

1 files changed, 25 insertions, 0 deletions

diff --git a/clang/test/CodeGenOpenCL/fpaccuracy.cl b/clang/test/CodeGenOpenCL/fpaccuracy.cl
new file mode 100644
index 00000000000..47fca696f9a
--- /dev/null
+++ b/clang/test/CodeGenOpenCL/fpaccuracy.cl
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 %s -emit-llvm -o - | FileCheck %s
+
+typedef __attribute__(( ext_vector_type(4) )) float float4;
+
+float spscalardiv(float a, float b) {
+  // CHECK: @spscalardiv
+  // CHECK: fdiv{{.*}}, !fpaccuracy ![[MD:[0-9]+]]
+  return a / b;
+}
+
+float4 spvectordiv(float4 a, float4 b) {
+  // CHECK: @spvectordiv
+  // CHECK: fdiv{{.*}}, !fpaccuracy ![[MD]]
+  return a / b;
+}
+
+#pragma OPENCL EXTENSION cl_khr_fp64 : enable
+
+double dpscalardiv(double a, double b) {
+  // CHECK: @dpscalardiv
+  // CHECK-NOT: !fpaccuracy
+  return a / b;
+}
+
+// CHECK: ![[MD]] = metadata !{i{{[0-9]+}} 5, i{{[0-9]+}} 2}