[llvm] [NVPTX] improve lowering for common byte-extraction operations. (PR #66945)

[Thomas Raoux via llvm-commits]

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@@ -0,0 +1,93 @@
+; RUN: llc < %s -march=nvptx64 -mcpu=sm_35 -verify-machineinstrs | FileCheck %s
+; RUN: %if ptxas %{ llc < %s -march=nvptx64 -mcpu=sm_35 | %ptxas-verify %}
+
+
+; CHECK-LABEL: test_v2i8
+; CHECK-DAG:        ld.param.u16    [[A:%rs[0-9+]]], [test_v2i8_param_0];
+; CHECK-DAG:        cvt.s16.s8      [[E0:%rs[0-9+]]], [[A]];
+; CHECK-DAG:        shr.s16         [[E1:%rs[0-9+]]], [[A]], 8;
+define i16  @test_v2i8(i16 %a) #0 {
+  %v = bitcast i16 %a to <2 x i8>
+  %r0 = extractelement <2 x i8> %v, i64 0
+  %r1 = extractelement <2 x i8> %v, i64 1
+  %r0i = sext i8 %r0 to i16
+  %r1i = sext i8 %r1 to i16
+  %r01 = add i16 %r0i, %r1i
+  ret i16 %r01
+}
+
+; CHECK-LABEL: test_v4i8
+; CHECK:            ld.param.u32    [[R:%r[0-9+]]], [test_v4i8_param_0];
+; CHECK-DAG:        cvt.s8.s32      [[E0:%rs[0-9+]]], [[R]];
+; CHECK-DAG:        bfe.s32         [[R1:%r[0-9+]]], [[R]], 8, 8;
+; CHECK-DAG:        cvt.s8.s32      [[E1:%rs[0-9+]]], [[R1]];
+; CHECK-DAG:        bfe.s32         [[R2:%r[0-9+]]], [[R]], 16, 8;
+; CHECK-DAG:        cvt.s8.s32      [[E2:%rs[0-9+]]], [[R2]];
+; CHECK-DAG:        bfe.s32         [[R3:%r[0-9+]]], [[R]], 24, 8;
+; CHECK-DAG:        cvt.s8.s32      [[E3:%rs[0-9+]]], [[R3]];
+define i16  @test_v4i8(i32 %a) #0 {
+  %v = bitcast i32 %a to <4 x i8>
+  %r0 = extractelement <4 x i8> %v, i64 0
+  %r1 = extractelement <4 x i8> %v, i64 1
+  %r2 = extractelement <4 x i8> %v, i64 2
+  %r3 = extractelement <4 x i8> %v, i64 3
+  %r0i = sext i8 %r0 to i16
+  %r1i = sext i8 %r1 to i16
+  %r2i = sext i8 %r2 to i16
+  %r3i = sext i8 %r3 to i16
+  %r01 = add i16 %r0i, %r1i
+  %r23 = add i16 %r2i, %r3i
+  %r = add i16 %r01, %r23
+  ret i16 %r
+}
+
+; CHECK-LABEL: test_v8i8
+; CHECK:       ld.param.u64    [[R:%rd[0-9+]]], [test_v8i8_param_0];
+; CHECK-DAG:        cvt.s8.s64      [[E0:%rs[0-9+]]], [[R]];
+; Element 1 is still extracted by trunc, shr 8, not sure why.
+; CHECK-DAG:        cvt.u16.u64     [[R01:%rs[0-9+]]], [[R]];
+; CHECK-DAG:        shr.s16         [[E1:%rs[0-9+]]], [[R01]], 8;
+; CHECK-DAG:        bfe.s64         [[RD2:%rd[0-9+]]], [[R]], 16, 8;
+; CHECK-DAG:        cvt.s8.s64      [[E2:%rs[0-9+]]], [[RD2]];
+; CHECK-DAG:        bfe.s64         [[RD3:%rd[0-9+]]], [[R]], 24, 8;
+; CHECK-DAG:        cvt.s8.s64      [[E3:%rs[0-9+]]], [[RD3]];
+; CHECK-DAG:        bfe.s64         [[RD4:%rd[0-9+]]], [[R]], 32, 8;
+; CHECK-DAG:        cvt.s8.s64      [[E4:%rs[0-9+]]], [[RD4]];
+; CHECK-DAG:        bfe.s64         [[RD5:%rd[0-9+]]], [[R]], 40, 8;
+; CHECK-DAG:        cvt.s8.s64      [[E5:%rs[0-9+]]], [[RD5]];
+; CHECK-DAG:        bfe.s64         [[RD6:%rd[0-9+]]], [[R]], 48, 8;
+; CHECK-DAG:        cvt.s8.s64      [[E6:%rs[0-9+]]], [[RD6]];
+; CHECK-DAG:        bfe.s64         [[RD7:%rd[0-9+]]], [[R]], 56, 8;
+; CHECK-DAG:        cvt.s8.s64      [[E7:%rs[0-9+]]], [[RD7]];
+
+define i16  @test_v8i8(i64 %a) #0 {
+  %v = bitcast i64 %a to <8 x i8>
+  %r0 = extractelement <8 x i8> %v, i64 0
+  %r1 = extractelement <8 x i8> %v, i64 1
+  %r2 = extractelement <8 x i8> %v, i64 2
+  %r3 = extractelement <8 x i8> %v, i64 3
+  %r4 = extractelement <8 x i8> %v, i64 4
+  %r5 = extractelement <8 x i8> %v, i64 5
+  %r6 = extractelement <8 x i8> %v, i64 6
+  %r7 = extractelement <8 x i8> %v, i64 7
+  %r0i = sext i8 %r0 to i16
+  %r1i = sext i8 %r1 to i16
+  %r2i = sext i8 %r2 to i16
+  %r3i = sext i8 %r3 to i16
+  %r4i = sext i8 %r4 to i16
+  %r5i = sext i8 %r5 to i16
+  %r6i = sext i8 %r6 to i16
+  %r7i = sext i8 %r7 to i16
+  %r01 = add i16 %r0i, %r1i
+  %r23 = add i16 %r2i, %r3i
+  %r45 = add i16 %r4i, %r5i
+  %r67 = add i16 %r6i, %r7i
+  %r0123 = add i16 %r01, %r23
+  %r4567 = add i16 %r45, %r67
+  %r = add i16 %r0123, %r4567
+  ret i16 %r
+}
+
+
+
+!0 = !{}
----------------
ThomasRaoux wrote:

remove.

https://github.com/llvm/llvm-project/pull/66945