[llvm] [AMDGPU] Ensure positive InstOffset for buffer operations (PR #145504)
Aleksandar Spasojevic via llvm-commits
llvm-commits at lists.llvm.org
Tue Jun 24 07:58:37 PDT 2025
https://github.com/aleksandar-amd updated https://github.com/llvm/llvm-project/pull/145504
>From 81fc7eba6d677bb1b50e2d9f11286d8675b89c25 Mon Sep 17 00:00:00 2001
From: Aleksandar Spasojevic <aleksandar.spasojevic at amd.com>
Date: Tue, 24 Jun 2025 13:33:12 +0200
Subject: [PATCH 1/2] [AMDGPU] Ensure positive InstOffset for buffer operations
GFX12+ buffer ops require positive InstOffset per AMD hardware spec.
Modified assembler/disassembler to reject negative buffer offsets.
---
.../AMDGPU/AsmParser/AMDGPUAsmParser.cpp | 15 +-
.../Disassembler/AMDGPUDisassembler.cpp | 15 +
llvm/test/MC/AMDGPU/gfx12_err.s | 258 ++++++++++++++++++
.../AMDGPU/gfx12_dasm_buffer_err.txt | 25 ++
4 files changed, 311 insertions(+), 2 deletions(-)
create mode 100644 llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt
diff --git a/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp b/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
index 30dcd6d81f16d..2f759eb2609f1 100644
--- a/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
+++ b/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
@@ -4464,12 +4464,13 @@ bool AMDGPUAsmParser::validateOffset(const MCInst &Inst,
return validateSMEMOffset(Inst, Operands);
const auto &Op = Inst.getOperand(OpNum);
+ // GFX12+ buffer ops: InstOffset is signed 24, but must be positive
if (isGFX12Plus() &&
(TSFlags & (SIInstrFlags::MUBUF | SIInstrFlags::MTBUF))) {
const unsigned OffsetSize = 24;
- if (!isIntN(OffsetSize, Op.getImm())) {
+ if (!isUIntN(OffsetSize - 1, Op.getImm())) {
Error(getFlatOffsetLoc(Operands),
- Twine("expected a ") + Twine(OffsetSize) + "-bit signed offset");
+ Twine("expected a ") + Twine(OffsetSize - 1) + "-bit positive offset for buffer ops");
return false;
}
} else {
@@ -4547,6 +4548,16 @@ bool AMDGPUAsmParser::validateSMEMOffset(const MCInst &Inst,
uint64_t Offset = Op.getImm();
bool IsBuffer = AMDGPU::getSMEMIsBuffer(Opcode);
+ // GFX12+ S_BUFFER_*: InstOffset is signed 24, but must be positive
+ if (isGFX12Plus() && IsBuffer) {
+ const unsigned OffsetSize = 24;
+ if (!isUIntN(OffsetSize, Offset)) {
+ Error(getSMEMOffsetLoc(Operands),
+ Twine("expected a ") + Twine(OffsetSize - 1) + "-bit positive offset for S_BUFFER ops");
+ return false;
+ }
+ return true;
+ }
if (AMDGPU::isLegalSMRDEncodedUnsignedOffset(getSTI(), Offset) ||
AMDGPU::isLegalSMRDEncodedSignedOffset(getSTI(), Offset, IsBuffer))
return true;
diff --git a/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp b/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
index 07a4292ef28bc..567d3e4ab6203 100644
--- a/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
+++ b/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
@@ -803,6 +803,21 @@ DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
}
}
+ // Validate buffer offset for GFX12+ - must be positive
+ if ((MCII->get(MI.getOpcode()).TSFlags &
+ (SIInstrFlags::MTBUF | SIInstrFlags::MUBUF)) &&
+ AMDGPU::isGFX12Plus(STI)) {
+ int OffsetIdx =
+ AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::offset);
+ if (OffsetIdx != -1) {
+ uint32_t Imm = MI.getOperand(OffsetIdx).getImm();
+ int64_t SignedOffset = SignExtend64<24>(Imm);
+ if (SignedOffset < 0) {
+ return MCDisassembler::Fail;
+ }
+ }
+ }
+
if (MCII->get(MI.getOpcode()).TSFlags &
(SIInstrFlags::MTBUF | SIInstrFlags::MUBUF)) {
int SWZOpIdx =
diff --git a/llvm/test/MC/AMDGPU/gfx12_err.s b/llvm/test/MC/AMDGPU/gfx12_err.s
index 9ddb91e25afe6..89278feb43ac3 100644
--- a/llvm/test/MC/AMDGPU/gfx12_err.s
+++ b/llvm/test/MC/AMDGPU/gfx12_err.s
@@ -125,3 +125,261 @@ s_alloc_vgpr exec
s_alloc_vgpr vcc
// GFX12-ERR: :[[@LINE-1]]:{{[0-9]+}}: error: invalid operand for instruction
+
+buffer_load_dword v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_dword v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_dwordx2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_dwordx3 v[0:2], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_dwordx4 v[0:3], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_short_d16 v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_format_d16_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_format_d16_xy v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_format_d16_xyz v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_format_d16_xyzw v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_short_d16_hi v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_format_d16_hi_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_sbyte_d16_hi v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_ubyte_d16_hi v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_sbyte_d16 v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_ubyte_d16 v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_sbyte v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_sshort v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_ubyte v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_load_ushort v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_byte v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_short v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_dword v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_dwordx2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_dwordx3 v[0:2], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_dwordx4 v[0:3], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_format_d16_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_format_d16_xy v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_format_d16_xyz v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_format_d16_xyzw v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_byte_d16_hi v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_short_d16_hi v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_store_format_d16_hi_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_add v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_add_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_and v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_and_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_cmpswap v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_cmpswap_x2 v[0:3], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_csub v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_dec v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_dec_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_inc v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_inc_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_fmax v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_smax v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_smax_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_umax v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_umax_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_fmin v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_smin v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_smin_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_umin v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_umin_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_or v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_or_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_sub v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_sub_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_swap v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_swap_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_xor v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+buffer_atomic_xor_x2 v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_d16_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_d16_xy v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_d16_xyz v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_d16_xyzw v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_xy v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_xyz v[0:2], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_load_format_xyzw v[0:3], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_d16_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_d16_xy v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_d16_xyz v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_d16_xyzw v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_x v0, off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_xy v[0:1], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_xyz v[0:2], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+tbuffer_store_format_xyzw v[0:3], off, s[4:7], s8 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for buffer ops
+
+s_buffer_load_b32 s5, s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_load_b64 s[10:11], s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_load_b96 s[20:22], s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_load_i8 s5, s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_load_u8 s5, s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_load_i16 s5, s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_load_u16 s5, s[4:7], s0 offset:-1
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
+
+s_buffer_prefetch_data s[20:23], -1, s10, 7
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
\ No newline at end of file
diff --git a/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt b/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt
new file mode 100644
index 0000000000000..d58a7e9b6116a
--- /dev/null
+++ b/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt
@@ -0,0 +1,25 @@
+# RUN: not llvm-mc -disassemble -triple=amdgcn -mcpu=gfx1200 -show-encoding %s 2>&1 | FileCheck --implicit-check-not=warning: --check-prefix=GFX12 %s
+
+# buffer_load_b32 v1, off, s[0:3], s4 offset:-1
+# GFX12: warning: invalid instruction encoding
+[0x04,0x00,0x05,0xc4,0x01,0x00,0x80,0x00,0xff,0xff,0xff,0xff]
+
+# buffer_load_b32 v0, off, s[4:7], s8 offset:-1
+# GFX12: warning: invalid instruction encoding
+[0x08,0x00,0x05,0xc4,0x00,0x08,0x80,0x00,0xff,0xff,0xff,0xff]
+
+# buffer_load_b64 v[0:1], off, s[4:7], s8 offset:-1
+# GFX12: warning: invalid instruction encoding
+[0x08,0x40,0x05,0xc4,0x00,0x08,0x80,0x00,0xff,0xff,0xff,0xff]
+
+# buffer_store_b32 v0, off, s[4:7], s8 offset:-1
+# GFX12: warning: invalid instruction encoding
+[0x08,0x80,0x06,0xc4,0x00,0x08,0x80,0x00,0xff,0xff,0xff,0xff]
+
+# buffer_atomic_add v0, off, s[4:7], s8 offset:-1
+# GFX12: warning: invalid instruction encoding
+[0x08,0x40,0x0d,0xc4,0x00,0x08,0x80,0x00,0xff,0xff,0xff,0xff]
+
+# tbuffer_load_format_x v0, off, s[4:7], s8 format:0 offset:-1
+# GFX12: warning: invalid instruction encoding
+[0x08,0x00,0x20,0xc4,0x00,0x08,0x00,0x00,0xff,0xff,0xff,0xff]
\ No newline at end of file
>From 3470988fff090783aca93a4b192eb01e79b9e1ae Mon Sep 17 00:00:00 2001
From: Aleksandar Spasojevic <aleksandar.spasojevic at amd.com>
Date: Tue, 24 Jun 2025 16:33:09 +0200
Subject: [PATCH 2/2] [AMDGPU] Fix buffer offset validation per PR feedback
Resolving comments from review.
---
.../AMDGPU/AsmParser/AMDGPUAsmParser.cpp | 23 ++++++++-----------
.../Disassembler/AMDGPUDisassembler.cpp | 5 ++--
.../Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp | 8 ++++++-
llvm/test/MC/AMDGPU/gfx12_err.s | 2 +-
.../AMDGPU/gfx12_dasm_buffer_err.txt | 2 +-
5 files changed, 20 insertions(+), 20 deletions(-)
diff --git a/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp b/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
index 2f759eb2609f1..e014d069b28db 100644
--- a/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
+++ b/llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp
@@ -4548,24 +4548,19 @@ bool AMDGPUAsmParser::validateSMEMOffset(const MCInst &Inst,
uint64_t Offset = Op.getImm();
bool IsBuffer = AMDGPU::getSMEMIsBuffer(Opcode);
- // GFX12+ S_BUFFER_*: InstOffset is signed 24, but must be positive
- if (isGFX12Plus() && IsBuffer) {
- const unsigned OffsetSize = 24;
- if (!isUIntN(OffsetSize, Offset)) {
- Error(getSMEMOffsetLoc(Operands),
- Twine("expected a ") + Twine(OffsetSize - 1) + "-bit positive offset for S_BUFFER ops");
- return false;
- }
- return true;
- }
if (AMDGPU::isLegalSMRDEncodedUnsignedOffset(getSTI(), Offset) ||
AMDGPU::isLegalSMRDEncodedSignedOffset(getSTI(), Offset, IsBuffer))
return true;
- Error(getSMEMOffsetLoc(Operands),
- isGFX12Plus() ? "expected a 24-bit signed offset"
- : (isVI() || IsBuffer) ? "expected a 20-bit unsigned offset"
- : "expected a 21-bit signed offset");
+ // Generate appropriate error message based on generation and buffer type
+ if (isGFX12Plus() && IsBuffer)
+ Error(getSMEMOffsetLoc(Operands),
+ "expected a 23-bit positive offset for S_BUFFER ops");
+ else
+ Error(getSMEMOffsetLoc(Operands),
+ isGFX12Plus() ? "expected a 24-bit signed offset"
+ : (isVI() || IsBuffer) ? "expected a 20-bit unsigned offset"
+ : "expected a 21-bit signed offset");
return false;
}
diff --git a/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp b/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
index 567d3e4ab6203..20c2468306e7e 100644
--- a/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
+++ b/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp
@@ -806,15 +806,14 @@ DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
// Validate buffer offset for GFX12+ - must be positive
if ((MCII->get(MI.getOpcode()).TSFlags &
(SIInstrFlags::MTBUF | SIInstrFlags::MUBUF)) &&
- AMDGPU::isGFX12Plus(STI)) {
+ isGFX12Plus()) {
int OffsetIdx =
AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::offset);
if (OffsetIdx != -1) {
uint32_t Imm = MI.getOperand(OffsetIdx).getImm();
int64_t SignedOffset = SignExtend64<24>(Imm);
- if (SignedOffset < 0) {
+ if (SignedOffset < 0)
return MCDisassembler::Fail;
- }
}
}
diff --git a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
index 0e5493259edb9..95bfeb30132ae 100644
--- a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
@@ -2945,8 +2945,14 @@ bool isLegalSMRDEncodedUnsignedOffset(const MCSubtargetInfo &ST,
bool isLegalSMRDEncodedSignedOffset(const MCSubtargetInfo &ST,
int64_t EncodedOffset, bool IsBuffer) {
- if (isGFX12Plus(ST))
+ if (isGFX12Plus(ST)) {
+ // GFX12+ S_BUFFER_*: InstOffset is signed 24, but must be positive (23-bit)
+ if (IsBuffer) {
+ constexpr const unsigned OffsetSize = 23;
+ return isUIntN(OffsetSize, EncodedOffset);
+ }
return isInt<24>(EncodedOffset);
+ }
return !IsBuffer && hasSMRDSignedImmOffset(ST) && isInt<21>(EncodedOffset);
}
diff --git a/llvm/test/MC/AMDGPU/gfx12_err.s b/llvm/test/MC/AMDGPU/gfx12_err.s
index 89278feb43ac3..a9972c03f7430 100644
--- a/llvm/test/MC/AMDGPU/gfx12_err.s
+++ b/llvm/test/MC/AMDGPU/gfx12_err.s
@@ -382,4 +382,4 @@ s_buffer_load_u16 s5, s[4:7], s0 offset:-1
// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
s_buffer_prefetch_data s[20:23], -1, s10, 7
-// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
\ No newline at end of file
+// GFX12-ERR: [[@LINE-1]]:{{[0-9]+}}: error: expected a 23-bit positive offset for S_BUFFER ops
diff --git a/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt b/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt
index d58a7e9b6116a..fc7b9d02619e5 100644
--- a/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt
+++ b/llvm/test/MC/Disassembler/AMDGPU/gfx12_dasm_buffer_err.txt
@@ -22,4 +22,4 @@
# tbuffer_load_format_x v0, off, s[4:7], s8 format:0 offset:-1
# GFX12: warning: invalid instruction encoding
-[0x08,0x00,0x20,0xc4,0x00,0x08,0x00,0x00,0xff,0xff,0xff,0xff]
\ No newline at end of file
+[0x08,0x00,0x20,0xc4,0x00,0x08,0x00,0x00,0xff,0xff,0xff,0xff]
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