AMDGPU: Push bitcasts through build_vector

This reduces the number of copies and reg_sequences
when using fp constant vectors. This significantly
reduces the code size in local-stack-alloc-bug.ll

llvm-svn: 281822

1 files changed, 69 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/AMDGPU/bitcast-vector-extract.ll b/llvm/test/CodeGen/AMDGPU/bitcast-vector-extract.ll
new file mode 100644
index 00000000000..2482fa761b1
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/bitcast-vector-extract.ll
@@ -0,0 +1,69 @@
+; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
+; RUN: llc -march=amdgcn -mcpu=tonga -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
+
+; The bitcast should be pushed through the bitcasts so the vectors can
+; be broken down and the shared components can be CSEd
+
+; GCN-LABEL: {{^}}store_bitcast_constant_v8i32_to_v8f32:
+; GCN: buffer_store_dwordx4
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+define void @store_bitcast_constant_v8i32_to_v8f32(<8 x float> addrspace(1)* %out, <8 x i32> %vec) {
+  %vec0.bc = bitcast <8 x i32> <i32 7, i32 7, i32 7, i32 7, i32 7, i32 7, i32 7, i32 8> to <8 x float>
+  store volatile <8 x float> %vec0.bc, <8 x float> addrspace(1)* %out
+
+  %vec1.bc = bitcast <8 x i32> <i32 7, i32 7, i32 7, i32 7, i32 7, i32 7, i32 7, i32 9> to <8 x float>
+  store volatile <8 x float> %vec1.bc, <8 x float> addrspace(1)* %out
+  ret void
+}
+
+; GCN-LABEL: {{^}}store_bitcast_constant_v4i64_to_v8f32:
+; GCN: buffer_store_dwordx4
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+define void @store_bitcast_constant_v4i64_to_v8f32(<8 x float> addrspace(1)* %out, <4 x i64> %vec) {
+  %vec0.bc = bitcast <4 x i64> <i64 7, i64 7, i64 7, i64 8> to <8 x float>
+  store volatile <8 x float> %vec0.bc, <8 x float> addrspace(1)* %out
+
+  %vec1.bc = bitcast <4 x i64> <i64 7, i64 7, i64 7, i64 9> to <8 x float>
+  store volatile <8 x float> %vec1.bc, <8 x float> addrspace(1)* %out
+  ret void
+}
+
+; GCN-LABEL: {{^}}store_bitcast_constant_v4i64_to_v4f64:
+; GCN: buffer_store_dwordx4
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+define void @store_bitcast_constant_v4i64_to_v4f64(<4 x double> addrspace(1)* %out, <4 x i64> %vec) {
+  %vec0.bc = bitcast <4 x i64> <i64 7, i64 7, i64 7, i64 8> to <4 x double>
+  store volatile <4 x double> %vec0.bc, <4 x double> addrspace(1)* %out
+
+  %vec1.bc = bitcast <4 x i64> <i64 7, i64 7, i64 7, i64 9> to <4 x double>
+  store volatile <4 x double> %vec1.bc, <4 x double> addrspace(1)* %out
+  ret void
+}
+
+; GCN-LABEL: {{^}}store_bitcast_constant_v8i32_to_v16i16:
+; GCN: buffer_store_dwordx4
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+; GCN-NOT: v_mov_b32
+; GCN: buffer_store_dwordx4
+define void @store_bitcast_constant_v8i32_to_v16i16(<8 x float> addrspace(1)* %out, <16 x i16> %vec) {
+  %vec0.bc = bitcast <16 x i16> <i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 8> to <8 x float>
+  store volatile <8 x float> %vec0.bc, <8 x float> addrspace(1)* %out
+
+  %vec1.bc = bitcast <16 x i16> <i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 7, i16 9> to <8 x float>
+  store volatile <8 x float> %vec1.bc, <8 x float> addrspace(1)* %out
+  ret void
+}