[llvm] 835c462 - [RISCV] Add test case showing failure to use GREVIW for i32 bitreverse if result is not sign extended. NFC

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2020-11-13T12:41:41-08:00
New Revision: 835c462eae739cf09877597f0c7da43b8aac4bdf

URL: https://github.com/llvm/llvm-project/commit/835c462eae739cf09877597f0c7da43b8aac4bdf
DIFF: https://github.com/llvm/llvm-project/commit/835c462eae739cf09877597f0c7da43b8aac4bdf.diff

LOG: [RISCV] Add test case showing failure to use GREVIW for i32 bitreverse if result is not sign extended. NFC

Added: 
    

Modified: 
    llvm/test/CodeGen/RISCV/rv64Zbp.ll

Removed: 
    


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diff  --git a/llvm/test/CodeGen/RISCV/rv64Zbp.ll b/llvm/test/CodeGen/RISCV/rv64Zbp.ll
index 3c8aa65909b2..95fde9fb2cf2 100644
--- a/llvm/test/CodeGen/RISCV/rv64Zbp.ll
+++ b/llvm/test/CodeGen/RISCV/rv64Zbp.ll
@@ -1126,6 +1126,115 @@ define signext i32 @bitreverse_i32(i32 signext %a) nounwind {
   ret i32 %1
 }
 
+; Similar to bitreverse_i32 but the result is not sign extended.
+; FIXME: We should use greviw here.
+define void @bitreverse_i32_nosext(i32 signext %a, i32* %x) nounwind {
+; RV64I-LABEL: bitreverse_i32_nosext:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    srli a2, a0, 24
+; RV64I-NEXT:    lui a3, 4080
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    srli a3, a0, 8
+; RV64I-NEXT:    addi a4, zero, 255
+; RV64I-NEXT:    slli a5, a4, 24
+; RV64I-NEXT:    and a3, a3, a5
+; RV64I-NEXT:    or a2, a3, a2
+; RV64I-NEXT:    srli a3, a0, 40
+; RV64I-NEXT:    lui a5, 16
+; RV64I-NEXT:    addiw a5, a5, -256
+; RV64I-NEXT:    and a3, a3, a5
+; RV64I-NEXT:    srli a5, a0, 56
+; RV64I-NEXT:    or a3, a3, a5
+; RV64I-NEXT:    or a6, a2, a3
+; RV64I-NEXT:    slli a3, a0, 8
+; RV64I-NEXT:    slli a5, a4, 32
+; RV64I-NEXT:    and a3, a3, a5
+; RV64I-NEXT:    slli a5, a0, 24
+; RV64I-NEXT:    slli a2, a4, 40
+; RV64I-NEXT:    and a2, a5, a2
+; RV64I-NEXT:    or a2, a2, a3
+; RV64I-NEXT:    slli a3, a0, 40
+; RV64I-NEXT:    slli a4, a4, 48
+; RV64I-NEXT:    and a3, a3, a4
+; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    or a0, a0, a3
+; RV64I-NEXT:    or a0, a0, a2
+; RV64I-NEXT:    or a0, a0, a6
+; RV64I-NEXT:    lui a2, 3855
+; RV64I-NEXT:    addiw a2, a2, 241
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -241
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, 241
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -241
+; RV64I-NEXT:    and a2, a0, a2
+; RV64I-NEXT:    slli a2, a2, 4
+; RV64I-NEXT:    lui a3, 1044721
+; RV64I-NEXT:    addiw a3, a3, -241
+; RV64I-NEXT:    slli a3, a3, 12
+; RV64I-NEXT:    addi a3, a3, 241
+; RV64I-NEXT:    slli a3, a3, 12
+; RV64I-NEXT:    addi a3, a3, -241
+; RV64I-NEXT:    slli a3, a3, 12
+; RV64I-NEXT:    addi a3, a3, 240
+; RV64I-NEXT:    and a0, a0, a3
+; RV64I-NEXT:    srli a0, a0, 4
+; RV64I-NEXT:    or a0, a0, a2
+; RV64I-NEXT:    lui a2, 13107
+; RV64I-NEXT:    addiw a2, a2, 819
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, 819
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, 819
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, 819
+; RV64I-NEXT:    and a2, a0, a2
+; RV64I-NEXT:    slli a2, a2, 2
+; RV64I-NEXT:    lui a3, 1035469
+; RV64I-NEXT:    addiw a3, a3, -819
+; RV64I-NEXT:    slli a3, a3, 12
+; RV64I-NEXT:    addi a3, a3, -819
+; RV64I-NEXT:    slli a3, a3, 12
+; RV64I-NEXT:    addi a3, a3, -819
+; RV64I-NEXT:    slli a3, a3, 12
+; RV64I-NEXT:    addi a3, a3, -820
+; RV64I-NEXT:    and a0, a0, a3
+; RV64I-NEXT:    srli a0, a0, 2
+; RV64I-NEXT:    or a0, a0, a2
+; RV64I-NEXT:    lui a2, 349525
+; RV64I-NEXT:    addiw a2, a2, 1365
+; RV64I-NEXT:    slli a2, a2, 32
+; RV64I-NEXT:    and a2, a0, a2
+; RV64I-NEXT:    slli a2, a2, 1
+; RV64I-NEXT:    lui a3, 873813
+; RV64I-NEXT:    addiw a3, a3, 1365
+; RV64I-NEXT:    slli a3, a3, 33
+; RV64I-NEXT:    and a0, a0, a3
+; RV64I-NEXT:    srli a0, a0, 1
+; RV64I-NEXT:    or a0, a0, a2
+; RV64I-NEXT:    srli a0, a0, 32
+; RV64I-NEXT:    sw a0, 0(a1)
+; RV64I-NEXT:    ret
+;
+; RV64IB-LABEL: bitreverse_i32_nosext:
+; RV64IB:       # %bb.0:
+; RV64IB-NEXT:    rev a0, a0
+; RV64IB-NEXT:    srli a0, a0, 32
+; RV64IB-NEXT:    sw a0, 0(a1)
+; RV64IB-NEXT:    ret
+;
+; RV64IBP-LABEL: bitreverse_i32_nosext:
+; RV64IBP:       # %bb.0:
+; RV64IBP-NEXT:    rev a0, a0
+; RV64IBP-NEXT:    srli a0, a0, 32
+; RV64IBP-NEXT:    sw a0, 0(a1)
+; RV64IBP-NEXT:    ret
+  %1 = tail call i32 @llvm.bitreverse.i32(i32 %a)
+  store i32 %1, i32* %x
+  ret void
+}
+
 declare i64 @llvm.bitreverse.i64(i64)
 
 define i64 @bitreverse_i64(i64 %a) nounwind {