[llvm] 3eadcb8 - [AMDGPU][MC][GFX9] Corrected SMEM decoding

[Dmitry Preobrazhensky via llvm-commits]

Author: Dmitry Preobrazhensky
Date: 2021-04-06T14:10:46+03:00
New Revision: 3eadcb86abd2259e398c9c1ff81d5509bfeeb7df

URL: https://github.com/llvm/llvm-project/commit/3eadcb86abd2259e398c9c1ff81d5509bfeeb7df
DIFF: https://github.com/llvm/llvm-project/commit/3eadcb86abd2259e398c9c1ff81d5509bfeeb7df.diff

LOG: [AMDGPU][MC][GFX9] Corrected SMEM decoding

Corrected SMEM decoding when IMM=0 and OFFSET>127

Fixed bug 49819 (https://bugs.llvm.org/show_bug.cgi?id=49819)

Differential Revision: https://reviews.llvm.org/D99804

Added: 
    

Modified: 
    llvm/lib/Target/AMDGPU/SMInstructions.td
    llvm/test/MC/Disassembler/AMDGPU/smem_gfx9.txt

Removed: 
    


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diff  --git a/llvm/lib/Target/AMDGPU/SMInstructions.td b/llvm/lib/Target/AMDGPU/SMInstructions.td
index 71890a008abda..3ecbdf519960e 100644
--- a/llvm/lib/Target/AMDGPU/SMInstructions.td
+++ b/llvm/lib/Target/AMDGPU/SMInstructions.td
@@ -515,7 +515,8 @@ class SMEM_Real_vi <bits<8> op, SM_Pseudo ps>
 
   // VI supports 20-bit unsigned offsets while GFX9+ supports 21-bit signed.
   // Offset value is corrected accordingly when offset is encoded/decoded.
-  let Inst{52-32} = !if(ps.has_offset, offset{20-0}, ?);
+  let Inst{38-32} = !if(ps.has_offset, offset{6-0}, ?);
+  let Inst{52-39} = !if(ps.has_offset, !if(imm, offset{20-7}, ?), ?);
 }
 
 multiclass SM_Real_Loads_vi<bits<8> op, string ps,

diff  --git a/llvm/test/MC/Disassembler/AMDGPU/smem_gfx9.txt b/llvm/test/MC/Disassembler/AMDGPU/smem_gfx9.txt
index 7ee7da90e7d0d..849736ef3549b 100644
--- a/llvm/test/MC/Disassembler/AMDGPU/smem_gfx9.txt
+++ b/llvm/test/MC/Disassembler/AMDGPU/smem_gfx9.txt
@@ -291,3 +291,16 @@
 
 # GFX9: s_atc_probe_buffer 1, s[8:11], -0x1 ; encoding: [0x44,0x00,0x9e,0xc0,0xff,0xff,0x1f,0x00]
 0x44,0x00,0x9e,0xc0,0xff,0xff,0x1f,0x00
+
+#===------------------------------------------------------------------------===#
+# Decoding of OFFSET>127 with IMM=0
+#===------------------------------------------------------------------------===#
+
+# GFX9: s_atomic_or s5, s[2:3], s15             ; encoding: [0x41,0x01,0x24,0xc2,0x0f,0x00,0x00,0x00]
+0x41,0x01,0x24,0xc2,0x8f,0x00,0x00,0x00
+
+# GFX9: s_atomic_or s5, s[2:3], exec_hi         ; encoding: [0x41,0x01,0x24,0xc2,0x7f,0x00,0x00,0x00]
+0x41,0x01,0x24,0xc2,0xff,0xff,0x00,0x00
+
+# GFX9: s_atomic_add_x2 s[34:35], exec, s11 glc ; encoding: [0xbf,0x08,0x89,0xc2,0x0b,0x00,0x00,0x00]
+0xbf,0x08,0x89,0xc2,0x0b,0x00,0x00,0x00