[NVPTX] Auto-upgrade some NVPTX intrinsics to LLVM target-generic code.

Summary:
Specifically, we upgrade llvm.nvvm.:

 * brev{32,64}
 * clz.{i,ll}
 * popc.{i,ll}
 * abs.{i,ll}
 * {min,max}.{i,ll,u,ull}
 * h2f

These either map directly to an existing LLVM target-generic
intrinsic or map to a simple LLVM target-generic idiom.

In all cases, we check that the code we generate is lowered to PTX as we
expect.

These builtins don't need to be backfilled in clang: They're not
accessible to user code from nvcc.

Reviewers: tra

Subscribers: majnemer, cfe-commits, llvm-commits, jholewinski

Differential Revision: https://reviews.llvm.org/D28793

llvm-svn: 292694

1 files changed, 102 insertions, 0 deletions

diff --git a/llvm/test/Assembler/auto_upgrade_nvvm_intrinsics.ll b/llvm/test/Assembler/auto_upgrade_nvvm_intrinsics.ll
new file mode 100644
index 00000000000..e8c298ddc7b
--- /dev/null
+++ b/llvm/test/Assembler/auto_upgrade_nvvm_intrinsics.ll
@@ -0,0 +1,102 @@
+; Test to make sure NVVM intrinsics are automatically upgraded.
+; RUN: llvm-as < %s | llvm-dis | FileCheck %s
+; RUN: verify-uselistorder %s
+
+declare i32 @llvm.nvvm.brev32(i32)
+declare i64 @llvm.nvvm.brev64(i64)
+declare i32 @llvm.nvvm.clz.i(i32)
+declare i32 @llvm.nvvm.clz.ll(i64)
+declare i32 @llvm.nvvm.popc.i(i32)
+declare i32 @llvm.nvvm.popc.ll(i64)
+declare float @llvm.nvvm.h2f(i16)
+
+declare i32 @llvm.nvvm.abs.i(i32)
+declare i64 @llvm.nvvm.abs.ll(i64)
+
+declare i32 @llvm.nvvm.max.i(i32, i32)
+declare i64 @llvm.nvvm.max.ll(i64, i64)
+declare i32 @llvm.nvvm.max.ui(i32, i32)
+declare i64 @llvm.nvvm.max.ull(i64, i64)
+declare i32 @llvm.nvvm.min.i(i32, i32)
+declare i64 @llvm.nvvm.min.ll(i64, i64)
+declare i32 @llvm.nvvm.min.ui(i32, i32)
+declare i64 @llvm.nvvm.min.ull(i64, i64)
+
+; CHECK-LABEL: @simple_upgrade
+define void @simple_upgrade(i32 %a, i64 %b, i16 %c) {
+; CHECK: call i32 @llvm.bitreverse.i32(i32 %a)
+  %r1 = call i32 @llvm.nvvm.brev32(i32 %a)
+
+; CHECK: call i64 @llvm.bitreverse.i64(i64 %b)
+  %r2 = call i64 @llvm.nvvm.brev64(i64 %b)
+
+; CHECK: call i32 @llvm.ctlz.i32(i32 %a, i1 false)
+  %r3 = call i32 @llvm.nvvm.clz.i(i32 %a)
+
+; CHECK: [[clz:%[a-zA-Z0-9.]+]] = call i64 @llvm.ctlz.i64(i64 %b, i1 false)
+; CHECK: trunc i64 [[clz]] to i32
+  %r4 = call i32 @llvm.nvvm.clz.ll(i64 %b)
+
+; CHECK: call i32 @llvm.ctpop.i32(i32 %a)
+  %r5 = call i32 @llvm.nvvm.popc.i(i32 %a)
+
+; CHECK: [[popc:%[a-zA-Z0-9.]+]] = call i64 @llvm.ctpop.i64(i64 %b)
+; CHECK: trunc i64 [[popc]] to i32
+  %r6 = call i32 @llvm.nvvm.popc.ll(i64 %b)
+
+; CHECK: call float @llvm.convert.from.fp16.f32(i16 %c)
+  %r7 = call float @llvm.nvvm.h2f(i16 %c)
+  ret void
+}
+
+; CHECK-LABEL @abs
+define void @abs(i32 %a, i64 %b) {
+; CHECK-DAG: [[negi:%[a-zA-Z0-9.]+]] = sub i32 0, %a
+; CHECK-DAG: [[cmpi:%[a-zA-Z0-9.]+]] = icmp sge i32 %a, 0
+; CHECK: select i1 [[cmpi]], i32 %a, i32 [[negi]]
+  %r1 = call i32 @llvm.nvvm.abs.i(i32 %a)
+
+; CHECK-DAG: [[negll:%[a-zA-Z0-9.]+]] = sub i64 0, %b
+; CHECK-DAG: [[cmpll:%[a-zA-Z0-9.]+]] = icmp sge i64 %b, 0
+; CHECK: select i1 [[cmpll]], i64 %b, i64 [[negll]]
+  %r2 = call i64 @llvm.nvvm.abs.ll(i64 %b)
+
+  ret void
+}
+
+; CHECK-LABEL: @min_max
+define void @min_max(i32 %a1, i32 %a2, i64 %b1, i64 %b2) {
+; CHECK: [[maxi:%[a-zA-Z0-9.]+]] = icmp sge i32 %a1, %a2
+; CHECK: select i1 [[maxi]], i32 %a1, i32 %a2
+  %r1 = call i32 @llvm.nvvm.max.i(i32 %a1, i32 %a2)
+
+; CHECK: [[maxll:%[a-zA-Z0-9.]+]] = icmp sge i64 %b1, %b2
+; CHECK: select i1 [[maxll]], i64 %b1, i64 %b2
+  %r2 = call i64 @llvm.nvvm.max.ll(i64 %b1, i64 %b2)
+
+; CHECK: [[maxui:%[a-zA-Z0-9.]+]] = icmp uge i32 %a1, %a2
+; CHECK: select i1 [[maxui]], i32 %a1, i32 %a2
+  %r3 = call i32 @llvm.nvvm.max.ui(i32 %a1, i32 %a2)
+
+; CHECK: [[maxull:%[a-zA-Z0-9.]+]] = icmp uge i64 %b1, %b2
+; CHECK: select i1 [[maxull]], i64 %b1, i64 %b2
+  %r4 = call i64 @llvm.nvvm.max.ull(i64 %b1, i64 %b2)
+
+; CHECK: [[mini:%[a-zA-Z0-9.]+]] = icmp sle i32 %a1, %a2
+; CHECK: select i1 [[mini]], i32 %a1, i32 %a2
+  %r5 = call i32 @llvm.nvvm.min.i(i32 %a1, i32 %a2)
+
+; CHECK: [[minll:%[a-zA-Z0-9.]+]] = icmp sle i64 %b1, %b2
+; CHECK: select i1 [[minll]], i64 %b1, i64 %b2
+  %r6 = call i64 @llvm.nvvm.min.ll(i64 %b1, i64 %b2)
+
+; CHECK: [[minui:%[a-zA-Z0-9.]+]] = icmp ule i32 %a1, %a2
+; CHECK: select i1 [[minui]], i32 %a1, i32 %a2
+  %r7 = call i32 @llvm.nvvm.min.ui(i32 %a1, i32 %a2)
+
+; CHECK: [[minull:%[a-zA-Z0-9.]+]] = icmp ule i64 %b1, %b2
+; CHECK: select i1 [[minull]], i64 %b1, i64 %b2
+  %r8 = call i64 @llvm.nvvm.min.ull(i64 %b1, i64 %b2)
+
+  ret void
+}