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[RISCV] For RV32C, disassembly of c.slli should fail when immediate > 31 #133713

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Merged
merged 1 commit into from
Mar 31, 2025
Merged

[RISCV] For RV32C, disassembly of c.slli should fail when immediate > 31 #133713

merged 1 commit into from
Mar 31, 2025

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paulhuggett
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@paulhuggett paulhuggett commented Mar 31, 2025 •
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Fix for #133712.

The change causes c.slli instructions whose immediate has bit 5 set to be rejected when disassembling RV32C. Added a test to exhaustively cover c.slli for 32 bit targets. A minor tweak to make the debug output a little more readable.

The spec. (20240411) says:

For RV32C, shamt[5] must be zero; the code points with shamt[5]=1 are designated for custom extensions. For RV32C and RV64C, the shift amount must be non-zero; the code points with shamt=0 are HINTs. For all base ISAs, the code points with rd=x0 are HINTs, except those with shamt[5]=1 in RV32C.

@paulhuggett
For RV32C, c.slli is valid when the immediate is in the range [1,31]
4c5418a 
The change causes immediates with bit 5 set to be rejected when
disassembling RV32C. Added a test to exhaustively cover c.slli for 32
and bit targets. Minor tweak to make the debug output a little more readable.
@llvmbot llvmbot added backend:RISC-V mc Machine (object) code labels Mar 31, 2025
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llvmbot commented Mar 31, 2025

@llvm/pr-subscribers-backend-risc-v

Author: Paul Bowen-Huggett (paulhuggett)

Changes

Fix for #133712.

The change causes c.slli instructions whose immediate has bit 5 to be rejected when disassembling RV32C. Added a test to exhaustively cover c.slli for 32 and bit targets. Minor tweak to make the debug output a little more readable.

Patch is 122.02 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/133713.diff

2 Files Affected:

  • (modified) llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp (+8-4)
  • (added) llvm/test/MC/Disassembler/RISCV/c_slli.txt (+3119)
diff --git a/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp b/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
index b46b72b4b73e9..b22a4a7246c23 100644
--- a/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
+++ b/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
@@ -558,8 +558,12 @@ static DecodeStatus decodeRVCInstrRdRs1UImm(MCInst &Inst, uint32_t Insn,
                                             const MCDisassembler *Decoder) {
   Inst.addOperand(MCOperand::createReg(RISCV::X0));
   Inst.addOperand(Inst.getOperand(0));
-  uint32_t UImm6 =
-      fieldFromInstruction(Insn, 12, 1) << 5 | fieldFromInstruction(Insn, 2, 5);
+
+  uint32_t UImm6 = fieldFromInstruction(Insn, 12, 1) << 5;
+  // On RV32C, uimm[5]=1 is reserved for custom extensions.
+  if (UImm6 != 0 && Decoder->getSubtargetInfo().hasFeature(RISCV::Feature32Bit))
+    return MCDisassembler::Fail;
+  UImm6 |= fieldFromInstruction(Insn, 2, 5);
   [[maybe_unused]] DecodeStatus Result =
       decodeUImmOperand<6>(Inst, UImm6, Address, Decoder);
   assert(Result == MCDisassembler::Success && "Invalid immediate");
@@ -784,7 +788,7 @@ DecodeStatus RISCVDisassembler::getInstruction16(MCInst &MI, uint64_t &Size,
     if (!Entry.haveContainedFeatures(STI.getFeatureBits()))
       continue;
 
-    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << "table:\n");
+    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << " table:\n");
     DecodeStatus Result =
         decodeInstruction(Entry.Table, MI, Insn, Address, this, STI);
     if (Result == MCDisassembler::Fail)
@@ -820,7 +824,7 @@ DecodeStatus RISCVDisassembler::getInstruction48(MCInst &MI, uint64_t &Size,
     if (!Entry.haveContainedFeatures(STI.getFeatureBits()))
       continue;
 
-    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << "table:\n");
+    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << " table:\n");
     DecodeStatus Result =
         decodeInstruction(Entry.Table, MI, Insn, Address, this, STI);
     if (Result == MCDisassembler::Fail)
diff --git a/llvm/test/MC/Disassembler/RISCV/c_slli.txt b/llvm/test/MC/Disassembler/RISCV/c_slli.txt
new file mode 100644
index 0000000000000..6e8dc4c05147f
--- /dev/null
+++ b/llvm/test/MC/Disassembler/RISCV/c_slli.txt
@@ -0,0 +1,3119 @@
+# This test verifies the disassembler's behavior for all C.LUI opcodes with the
+# exception of those assigned to C.ADDI16SP
+#
+# RUN: llvm-mc --disassemble -triple=riscv32 -mattr=+c -M no-aliases \
+# RUN:     --show-encoding < %s | FileCheck --check-prefixes=GOOD %s
+#
+# RUN: llvm-mc --disassemble -triple=riscv64 -mattr=+c -M no-aliases \
+# RUN:     --show-encoding < %s | FileCheck --check-prefixes=GOOD,GOOD64 %s
+#
+# RUN: llvm-mc --disassemble -triple=riscv32 -mattr=+c -M no-aliases \
+# RUN:     --show-encoding < %s 2>&1 | FileCheck --check-prefix=BAD32 %s
+#
+# RUN: llvm-mc --disassemble -triple=riscv32  -mattr=+c -mattr=+no-rvc-hints \
+# RUN:     -M no-aliases --show-encoding < %s 2>&1 | \
+# RUN:   FileCheck --check-prefix=NOHINTS %s
+
+0x06 0x00 # GOOD: c.slli zero, 1
+0x06 0x00 # NOHINTS: invalid instruction encoding
+0x0A 0x00 # GOOD: c.slli zero, 2
+0x0A 0x00 # NOHINTS: invalid instruction encoding
+0x0E 0x00 # GOOD: c.slli zero, 3
+0x0E 0x00 # NOHINTS: invalid instruction encoding
+0x12 0x00 # GOOD: c.slli zero, 4
+0x12 0x00 # NOHINTS: invalid instruction encoding
+0x16 0x00 # GOOD: c.slli zero, 5
+0x16 0x00 # NOHINTS: invalid instruction encoding
+0x1A 0x00 # GOOD: c.slli zero, 6
+0x1A 0x00 # NOHINTS: invalid instruction encoding
+0x1E 0x00 # GOOD: c.slli zero, 7
+0x1E 0x00 # NOHINTS: invalid instruction encoding
+0x22 0x00 # GOOD: c.slli zero, 8
+0x22 0x00 # NOHINTS: invalid instruction encoding
+0x26 0x00 # GOOD: c.slli zero, 9
+0x26 0x00 # NOHINTS: invalid instruction encoding
+0x2A 0x00 # GOOD: c.slli zero, 10
+0x2A 0x00 # NOHINTS: invalid instruction encoding
+0x2E 0x00 # GOOD: c.slli zero, 11
+0x2E 0x00 # NOHINTS: invalid instruction encoding
+0x32 0x00 # GOOD: c.slli zero, 12
+0x32 0x00 # NOHINTS: invalid instruction encoding
+0x36 0x00 # GOOD: c.slli zero, 13
+0x36 0x00 # NOHINTS: invalid instruction encoding
+0x3A 0x00 # GOOD: c.slli zero, 14
+0x3A 0x00 # NOHINTS: invalid instruction encoding
+0x3E 0x00 # GOOD: c.slli zero, 15
+0x3E 0x00 # NOHINTS: invalid instruction encoding
+0x42 0x00 # GOOD: c.slli zero, 16
+0x42 0x00 # NOHINTS: invalid instruction encoding
+0x46 0x00 # GOOD: c.slli zero, 17
+0x46 0x00 # NOHINTS: invalid instruction encoding
+0x4A 0x00 # GOOD: c.slli zero, 18
+0x4A 0x00 # NOHINTS: invalid instruction encoding
+0x4E 0x00 # GOOD: c.slli zero, 19
+0x4E 0x00 # NOHINTS: invalid instruction encoding
+0x52 0x00 # GOOD: c.slli zero, 20
+0x52 0x00 # NOHINTS: invalid instruction encoding
+0x56 0x00 # GOOD: c.slli zero, 21
+0x56 0x00 # NOHINTS: invalid instruction encoding
+0x5A 0x00 # GOOD: c.slli zero, 22
+0x5A 0x00 # NOHINTS: invalid instruction encoding
+0x5E 0x00 # GOOD: c.slli zero, 23
+0x5E 0x00 # NOHINTS: invalid instruction encoding
+0x62 0x00 # GOOD: c.slli zero, 24
+0x62 0x00 # NOHINTS: invalid instruction encoding
+0x66 0x00 # GOOD: c.slli zero, 25
+0x66 0x00 # NOHINTS: invalid instruction encoding
+0x6A 0x00 # GOOD: c.slli zero, 26
+0x6A 0x00 # NOHINTS: invalid instruction encoding
+0x6E 0x00 # GOOD: c.slli zero, 27
+0x6E 0x00 # NOHINTS: invalid instruction encoding
+0x72 0x00 # GOOD: c.slli zero, 28
+0x72 0x00 # NOHINTS: invalid instruction encoding
+0x76 0x00 # GOOD: c.slli zero, 29
+0x76 0x00 # NOHINTS: invalid instruction encoding
+0x7A 0x00 # GOOD: c.slli zero, 30
+0x7A 0x00 # NOHINTS: invalid instruction encoding
+0x7E 0x00 # GOOD: c.slli zero, 31
+0x7E 0x00 # NOHINTS: invalid instruction encoding
+0x02 0x10 # BAD32: invalid instruction encoding
+0x02 0x10 # GOOD64: c.slli zero, 32
+0x02 0x10 # NOHINTS: invalid instruction encoding
+0x06 0x10 # BAD32: invalid instruction encoding
+0x06 0x10 # GOOD64: c.slli zero, 33
+0x06 0x10 # NOHINTS: invalid instruction encoding
+0x0A 0x10 # BAD32: invalid instruction encoding
+0x0A 0x10 # GOOD64: c.slli zero, 34
+0x0A 0x10 # NOHINTS: invalid instruction encoding
+0x0E 0x10 # BAD32: invalid instruction encoding
+0x0E 0x10 # GOOD64: c.slli zero, 35
+0x0E 0x10 # NOHINTS: invalid instruction encoding
+0x12 0x10 # BAD32: invalid instruction encoding
+0x12 0x10 # GOOD64: c.slli zero, 36
+0x12 0x10 # NOHINTS: invalid instruction encoding
+0x16 0x10 # BAD32: invalid instruction encoding
+0x16 0x10 # GOOD64: c.slli zero, 37
+0x16 0x10 # NOHINTS: invalid instruction encoding
+0x1A 0x10 # BAD32: invalid instruction encoding
+0x1A 0x10 # GOOD64: c.slli zero, 38
+0x1A 0x10 # NOHINTS: invalid instruction encoding
+0x1E 0x10 # BAD32: invalid instruction encoding
+0x1E 0x10 # GOOD64: c.slli zero, 39
+0x1E 0x10 # NOHINTS: invalid instruction encoding
+0x22 0x10 # BAD32: invalid instruction encoding
+0x22 0x10 # GOOD64: c.slli zero, 40
+0x22 0x10 # NOHINTS: invalid instruction encoding
+0x26 0x10 # BAD32: invalid instruction encoding
+0x26 0x10 # GOOD64: c.slli zero, 41
+0x26 0x10 # NOHINTS: invalid instruction encoding
+0x2A 0x10 # BAD32: invalid instruction encoding
+0x2A 0x10 # GOOD64: c.slli zero, 42
+0x2A 0x10 # NOHINTS: invalid instruction encoding
+0x2E 0x10 # BAD32: invalid instruction encoding
+0x2E 0x10 # GOOD64: c.slli zero, 43
+0x2E 0x10 # NOHINTS: invalid instruction encoding
+0x32 0x10 # BAD32: invalid instruction encoding
+0x32 0x10 # GOOD64: c.slli zero, 44
+0x32 0x10 # NOHINTS: invalid instruction encoding
+0x36 0x10 # BAD32: invalid instruction encoding
+0x36 0x10 # GOOD64: c.slli zero, 45
+0x36 0x10 # NOHINTS: invalid instruction encoding
+0x3A 0x10 # BAD32: invalid instruction encoding
+0x3A 0x10 # GOOD64: c.slli zero, 46
+0x3A 0x10 # NOHINTS: invalid instruction encoding
+0x3E 0x10 # BAD32: invalid instruction encoding
+0x3E 0x10 # GOOD64: c.slli zero, 47
+0x3E 0x10 # NOHINTS: invalid instruction encoding
+0x42 0x10 # BAD32: invalid instruction encoding
+0x42 0x10 # GOOD64: c.slli zero, 48
+0x42 0x10 # NOHINTS: invalid instruction encoding
+0x46 0x10 # BAD32: invalid instruction encoding
+0x46 0x10 # GOOD64: c.slli zero, 49
+0x46 0x10 # NOHINTS: invalid instruction encoding
+0x4A 0x10 # BAD32: invalid instruction encoding
+0x4A 0x10 # GOOD64: c.slli zero, 50
+0x4A 0x10 # NOHINTS: invalid instruction encoding
+0x4E 0x10 # BAD32: invalid instruction encoding
+0x4E 0x10 # GOOD64: c.slli zero, 51
+0x4E 0x10 # NOHINTS: invalid instruction encoding
+0x52 0x10 # BAD32: invalid instruction encoding
+0x52 0x10 # GOOD64: c.slli zero, 52
+0x52 0x10 # NOHINTS: invalid instruction encoding
+0x56 0x10 # BAD32: invalid instruction encoding
+0x56 0x10 # GOOD64: c.slli zero, 53
+0x56 0x10 # NOHINTS: invalid instruction encoding
+0x5A 0x10 # BAD32: invalid instruction encoding
+0x5A 0x10 # GOOD64: c.slli zero, 54
+0x5A 0x10 # NOHINTS: invalid instruction encoding
+0x5E 0x10 # BAD32: invalid instruction encoding
+0x5E 0x10 # GOOD64: c.slli zero, 55
+0x5E 0x10 # NOHINTS: invalid instruction encoding
+0x62 0x10 # BAD32: invalid instruction encoding
+0x62 0x10 # GOOD64: c.slli zero, 56
+0x62 0x10 # NOHINTS: invalid instruction encoding
+0x66 0x10 # BAD32: invalid instruction encoding
+0x66 0x10 # GOOD64: c.slli zero, 57
+0x66 0x10 # NOHINTS: invalid instruction encoding
+0x6A 0x10 # BAD32: invalid instruction encoding
+0x6A 0x10 # GOOD64: c.slli zero, 58
+0x6A 0x10 # NOHINTS: invalid instruction encoding
+0x6E 0x10 # BAD32: invalid instruction encoding
+0x6E 0x10 # GOOD64: c.slli zero, 59
+0x6E 0x10 # NOHINTS: invalid instruction encoding
+0x72 0x10 # BAD32: invalid instruction encoding
+0x72 0x10 # GOOD64: c.slli zero, 60
+0x72 0x10 # NOHINTS: invalid instruction encoding
+0x76 0x10 # BAD32: invalid instruction encoding
+0x76 0x10 # GOOD64: c.slli zero, 61
+0x76 0x10 # NOHINTS: invalid instruction encoding
+0x7A 0x10 # BAD32: invalid instruction encoding
+0x7A 0x10 # GOOD64: c.slli zero, 62
+0x7A 0x10 # NOHINTS: invalid instruction encoding
+0x7E 0x10 # BAD32: invalid instruction encoding
+0x7E 0x10 # GOOD64: c.slli zero, 63
+0x7E 0x10 # NOHINTS: invalid instruction encoding
+0x86 0x00 # GOOD: c.slli ra, 1
+0x8A 0x00 # GOOD: c.slli ra, 2
+0x8E 0x00 # GOOD: c.slli ra, 3
+0x92 0x00 # GOOD: c.slli ra, 4
+0x96 0x00 # GOOD: c.slli ra, 5
+0x9A 0x00 # GOOD: c.slli ra, 6
+0x9E 0x00 # GOOD: c.slli ra, 7
+0xA2 0x00 # GOOD: c.slli ra, 8
+0xA6 0x00 # GOOD: c.slli ra, 9
+0xAA 0x00 # GOOD: c.slli ra, 10
+0xAE 0x00 # GOOD: c.slli ra, 11
+0xB2 0x00 # GOOD: c.slli ra, 12
+0xB6 0x00 # GOOD: c.slli ra, 13
+0xBA 0x00 # GOOD: c.slli ra, 14
+0xBE 0x00 # GOOD: c.slli ra, 15
+0xC2 0x00 # GOOD: c.slli ra, 16
+0xC6 0x00 # GOOD: c.slli ra, 17
+0xCA 0x00 # GOOD: c.slli ra, 18
+0xCE 0x00 # GOOD: c.slli ra, 19
+0xD2 0x00 # GOOD: c.slli ra, 20
+0xD6 0x00 # GOOD: c.slli ra, 21
+0xDA 0x00 # GOOD: c.slli ra, 22
+0xDE 0x00 # GOOD: c.slli ra, 23
+0xE2 0x00 # GOOD: c.slli ra, 24
+0xE6 0x00 # GOOD: c.slli ra, 25
+0xEA 0x00 # GOOD: c.slli ra, 26
+0xEE 0x00 # GOOD: c.slli ra, 27
+0xF2 0x00 # GOOD: c.slli ra, 28
+0xF6 0x00 # GOOD: c.slli ra, 29
+0xFA 0x00 # GOOD: c.slli ra, 30
+0xFE 0x00 # GOOD: c.slli ra, 31
+0x82 0x10 # BAD32: invalid instruction encoding
+0x82 0x10 # GOOD64: c.slli ra, 32
+0x86 0x10 # BAD32: invalid instruction encoding
+0x86 0x10 # GOOD64: c.slli ra, 33
+0x8A 0x10 # BAD32: invalid instruction encoding
+0x8A 0x10 # GOOD64: c.slli ra, 34
+0x8E 0x10 # BAD32: invalid instruction encoding
+0x8E 0x10 # GOOD64: c.slli ra, 35
+0x92 0x10 # BAD32: invalid instruction encoding
+0x92 0x10 # GOOD64: c.slli ra, 36
+0x96 0x10 # BAD32: invalid instruction encoding
+0x96 0x10 # GOOD64: c.slli ra, 37
+0x9A 0x10 # BAD32: invalid instruction encoding
+0x9A 0x10 # GOOD64: c.slli ra, 38
+0x9E 0x10 # BAD32: invalid instruction encoding
+0x9E 0x10 # GOOD64: c.slli ra, 39
+0xA2 0x10 # BAD32: invalid instruction encoding
+0xA2 0x10 # GOOD64: c.slli ra, 40
+0xA6 0x10 # BAD32: invalid instruction encoding
+0xA6 0x10 # GOOD64: c.slli ra, 41
+0xAA 0x10 # BAD32: invalid instruction encoding
+0xAA 0x10 # GOOD64: c.slli ra, 42
+0xAE 0x10 # BAD32: invalid instruction encoding
+0xAE 0x10 # GOOD64: c.slli ra, 43
+0xB2 0x10 # BAD32: invalid instruction encoding
+0xB2 0x10 # GOOD64: c.slli ra, 44
+0xB6 0x10 # BAD32: invalid instruction encoding
+0xB6 0x10 # GOOD64: c.slli ra, 45
+0xBA 0x10 # BAD32: invalid instruction encoding
+0xBA 0x10 # GOOD64: c.slli ra, 46
+0xBE 0x10 # BAD32: invalid instruction encoding
+0xBE 0x10 # GOOD64: c.slli ra, 47
+0xC2 0x10 # BAD32: invalid instruction encoding
+0xC2 0x10 # GOOD64: c.slli ra, 48
+0xC6 0x10 # BAD32: invalid instruction encoding
+0xC6 0x10 # GOOD64: c.slli ra, 49
+0xCA 0x10 # BAD32: invalid instruction encoding
+0xCA 0x10 # GOOD64: c.slli ra, 50
+0xCE 0x10 # BAD32: invalid instruction encoding
+0xCE 0x10 # GOOD64: c.slli ra, 51
+0xD2 0x10 # BAD32: invalid instruction encoding
+0xD2 0x10 # GOOD64: c.slli ra, 52
+0xD6 0x10 # BAD32: invalid instruction encoding
+0xD6 0x10 # GOOD64: c.slli ra, 53
+0xDA 0x10 # BAD32: invalid instruction encoding
+0xDA 0x10 # GOOD64: c.slli ra, 54
+0xDE 0x10 # BAD32: invalid instruction encoding
+0xDE 0x10 # GOOD64: c.slli ra, 55
+0xE2 0x10 # BAD32: invalid instruction encoding
+0xE2 0x10 # GOOD64: c.slli ra, 56
+0xE6 0x10 # BAD32: invalid instruction encoding
+0xE6 0x10 # GOOD64: c.slli ra, 57
+0xEA 0x10 # BAD32: invalid instruction encoding
+0xEA 0x10 # GOOD64: c.slli ra, 58
+0xEE 0x10 # BAD32: invalid instruction encoding
+0xEE 0x10 # GOOD64: c.slli ra, 59
+0xF2 0x10 # BAD32: invalid instruction encoding
+0xF2 0x10 # GOOD64: c.slli ra, 60
+0xF6 0x10 # BAD32: invalid instruction encoding
+0xF6 0x10 # GOOD64: c.slli ra, 61
+0xFA 0x10 # BAD32: invalid instruction encoding
+0xFA 0x10 # GOOD64: c.slli ra, 62
+0xFE 0x10 # BAD32: invalid instruction encoding
+0xFE 0x10 # GOOD64: c.slli ra, 63
+0x06 0x01 # GOOD: c.slli sp, 1
+0x0A 0x01 # GOOD: c.slli sp, 2
+0x0E 0x01 # GOOD: c.slli sp, 3
+0x12 0x01 # GOOD: c.slli sp, 4
+0x16 0x01 # GOOD: c.slli sp, 5
+0x1A 0x01 # GOOD: c.slli sp, 6
+0x1E 0x01 # GOOD: c.slli sp, 7
+0x22 0x01 # GOOD: c.slli sp, 8
+0x26 0x01 # GOOD: c.slli sp, 9
+0x2A 0x01 # GOOD: c.slli sp, 10
+0x2E 0x01 # GOOD: c.slli sp, 11
+0x32 0x01 # GOOD: c.slli sp, 12
+0x36 0x01 # GOOD: c.slli sp, 13
+0x3A 0x01 # GOOD: c.slli sp, 14
+0x3E 0x01 # GOOD: c.slli sp, 15
+0x42 0x01 # GOOD: c.slli sp, 16
+0x46 0x01 # GOOD: c.slli sp, 17
+0x4A 0x01 # GOOD: c.slli sp, 18
+0x4E 0x01 # GOOD: c.slli sp, 19
+0x52 0x01 # GOOD: c.slli sp, 20
+0x56 0x01 # GOOD: c.slli sp, 21
+0x5A 0x01 # GOOD: c.slli sp, 22
+0x5E 0x01 # GOOD: c.slli sp, 23
+0x62 0x01 # GOOD: c.slli sp, 24
+0x66 0x01 # GOOD: c.slli sp, 25
+0x6A 0x01 # GOOD: c.slli sp, 26
+0x6E 0x01 # GOOD: c.slli sp, 27
+0x72 0x01 # GOOD: c.slli sp, 28
+0x76 0x01 # GOOD: c.slli sp, 29
+0x7A 0x01 # GOOD: c.slli sp, 30
+0x7E 0x01 # GOOD: c.slli sp, 31
+0x02 0x11 # BAD32: invalid instruction encoding
+0x02 0x11 # GOOD64: c.slli sp, 32
+0x06 0x11 # BAD32: invalid instruction encoding
+0x06 0x11 # GOOD64: c.slli sp, 33
+0x0A 0x11 # BAD32: invalid instruction encoding
+0x0A 0x11 # GOOD64: c.slli sp, 34
+0x0E 0x11 # BAD32: invalid instruction encoding
+0x0E 0x11 # GOOD64: c.slli sp, 35
+0x12 0x11 # BAD32: invalid instruction encoding
+0x12 0x11 # GOOD64: c.slli sp, 36
+0x16 0x11 # BAD32: invalid instruction encoding
+0x16 0x11 # GOOD64: c.slli sp, 37
+0x1A 0x11 # BAD32: invalid instruction encoding
+0x1A 0x11 # GOOD64: c.slli sp, 38
+0x1E 0x11 # BAD32: invalid instruction encoding
+0x1E 0x11 # GOOD64: c.slli sp, 39
+0x22 0x11 # BAD32: invalid instruction encoding
+0x22 0x11 # GOOD64: c.slli sp, 40
+0x26 0x11 # BAD32: invalid instruction encoding
+0x26 0x11 # GOOD64: c.slli sp, 41
+0x2A 0x11 # BAD32: invalid instruction encoding
+0x2A 0x11 # GOOD64: c.slli sp, 42
+0x2E 0x11 # BAD32: invalid instruction encoding
+0x2E 0x11 # GOOD64: c.slli sp, 43
+0x32 0x11 # BAD32: invalid instruction encoding
+0x32 0x11 # GOOD64: c.slli sp, 44
+0x36 0x11 # BAD32: invalid instruction encoding
+0x36 0x11 # GOOD64: c.slli sp, 45
+0x3A 0x11 # BAD32: invalid instruction encoding
+0x3A 0x11 # GOOD64: c.slli sp, 46
+0x3E 0x11 # BAD32: invalid instruction encoding
+0x3E 0x11 # GOOD64: c.slli sp, 47
+0x42 0x11 # BAD32: invalid instruction encoding
+0x42 0x11 # GOOD64: c.slli sp, 48
+0x46 0x11 # BAD32: invalid instruction encoding
+0x46 0x11 # GOOD64: c.slli sp, 49
+0x4A 0x11 # BAD32: invalid instruction encoding
+0x4A 0x11 # GOOD64: c.slli sp, 50
+0x4E 0x11 # BAD32: invalid instruction encoding
+0x4E 0x11 # GOOD64: c.slli sp, 51
+0x52 0x11 # BAD32: invalid instruction encoding
+0x52 0x11 # GOOD64: c.slli sp, 52
+0x56 0x11 # BAD32: invalid instruction encoding
+0x56 0x11 # GOOD64: c.slli sp, 53
+0x5A 0x11 # BAD32: invalid instruction encoding
+0x5A 0x11 # GOOD64: c.slli sp, 54
+0x5E 0x11 # BAD32: invalid instruction encoding
+0x5E 0x11 # GOOD64: c.slli sp, 55
+0x62 0x11 # BAD32: invalid instruction encoding
+0x62 0x11 # GOOD64: c.slli sp, 56
+0x66 0x11 # BAD32: invalid instruction encoding
+0x66 0x11 # GOOD64: c.slli sp, 57
+0x6A 0x11 # BAD32: invalid instruction encoding
+0x6A 0x11 # GOOD64: c.slli sp, 58
+0x6E 0x11 # BAD32: invalid instruction encoding
+0x6E 0x11 # GOOD64: c.slli sp, 59
+0x72 0x11 # BAD32: invalid instruction encoding
+0x72 0x11 # GOOD64: c.slli sp, 60
+0x76 0x11 # BAD32: invalid instruction encoding
+0x76 0x11 # GOOD64: c.slli sp, 61
+0x7A 0x11 # BAD32: invalid instruction encoding
+0x7A 0x11 # GOOD64: c.slli sp, 62
+0x7E 0x11 # BAD32: invalid instruction encoding
+0x7E 0x11 # GOOD64: c.slli sp, 63
+0x86 0x01 # GOOD: c.slli gp, 1
+0x8A 0x01 # GOOD: c.slli gp, 2
+0x8E 0x01 # GOOD: c.slli gp, 3
+0x92 0x01 # GOOD: c.slli gp, 4
+0x96 0x01 # GOOD: c.slli gp, 5
+0x9A 0x01 # GOOD: c.slli gp, 6
+0x9E 0x01 # GOOD: c.slli gp, 7
+0xA2 0x01 # GOOD: c.slli gp, 8
+0xA6 0x01 # GOOD: c.slli gp, 9
+0xAA 0x01 # GOOD: c.slli gp, 10
+0xAE 0x01 # GOOD: c.slli gp, 11
+0xB2 0x01 # GOOD: c.slli gp, 12
+0xB6 0x01 # GOOD: c.slli gp, 13
+0xBA 0x01 # GOOD: c.slli gp, 14
+0xBE 0x01 # GOOD: c.slli gp, 15
+0xC2 0x01 # GOOD: c.slli gp, 16
+0xC6 0x01 # GOOD: c.slli gp, 17
+0xCA 0x01 # GOOD: c.slli gp, 18
+0xCE 0x01 # GOOD: c.slli gp, 19
+0xD2 0x01 # GOOD: c.slli gp, 20
+0xD6 0x01 # GOOD: c.slli gp, 21
+0xDA 0x01 # GOOD: c.slli gp, 22
+0xDE 0x01 # GOOD: c.slli gp, 23
+0xE2 0x01 # GOOD: c.slli gp, 24
+0xE6 0x01 # GOOD: c.slli gp, 25
+0xEA 0x01 # GOOD: c.slli gp, 26
+0xEE 0x01 # GOOD: c.slli gp, 27
+0xF2 0x01 # GOOD: c.slli gp, 28
+0xF6 0x01 # GOOD: c.slli gp, 29
+0xFA 0x01 # GOOD: c.slli gp, 30
+0xFE 0x01 # GOOD: c.slli gp, 31
+0x82 0x11 # BAD32: invalid instruction encoding
+0x82 0x11 # GOOD64: c.slli gp, 32
+0x86 0x11 # BAD32: invalid instruction encoding
+0x86 0x11 # GOOD64: c.slli gp, 33
+0x8A 0x11 # BAD32: invalid instruction encoding
+0x8A 0x11 # GOOD64: c.slli gp, 34
+0x8E 0x11 # BAD32: invalid instruction encoding
+0x8E 0x11 # GOOD64: c.slli gp, 35
+0x92 0x11 # BAD32: invalid instruction encoding
+0x92 0x11 # GOOD64: c.slli gp, 36
+0x96 0x11 # BAD32: invalid instruction encoding
+0x96 0x11 # GOOD64: c.slli gp, 37
+0x9A 0x11 # BAD32: invalid instruction encoding
+0x9A 0x11 # GOOD64: c.slli gp, 38
+0x9E 0x11 # BAD32: invalid instruction encoding
+0x9E 0x11 # GOOD64: c.slli gp, 39
+0xA2 0x11 # BAD32: invalid instruction encoding
+0xA2 0x11 # GOOD64: c.slli gp, 40
+0xA6 0x11 # BAD32: invalid instruction encoding
+0xA6 0x11 # GOOD64: c.slli gp, 41
+0xAA 0x11 # BAD32: invalid instruction encoding
+0xAA 0x11 # GOOD64: c.slli gp, 42
+0xAE 0x11 # BAD32: invalid instruction encoding
+0xAE 0x11 # GOOD64: c.slli gp, 43
+0xB2 0x11 # BAD32: invalid instruction encoding
+0xB2 0x11 # GOOD64: c.slli gp, 44
+0xB6 0x11 # BAD32: invalid instruction encoding
+0xB6 0x11 # GOOD64: c.slli gp, 45
+0xBA 0x11 # BAD32: invalid instruction encoding
+0xBA 0x11 # GOOD64: c.slli gp, 46
+0xBE 0x11 # BAD32: invalid instruction encoding
+0xBE 0x11 # GOOD64: c.slli gp, 47
+0xC2 0x11 # BAD32: invalid instruction encoding
+0xC2 0x11 # GOOD64: c.slli gp, 48
+0xC6 0x11 # BAD32: invalid instruction encoding
+0xC6 0x11 # GOOD64: c.slli gp, 49
+0xCA 0x11 # BAD32: invalid instruction encoding
+0xCA 0x11 # GOOD64: c.slli gp, 50
+0xCE 0x11 # BAD32: invalid instruction encoding
+0xCE 0x11 # GOOD64: c.slli gp, 51
+0xD2 0x11 # BAD32: invalid instruction encoding
+0xD2 0x11 # GOOD64: c.slli gp, 52
+0xD6 0x11 # BAD32: invalid instruction encoding
+0xD6 0x11 # GOOD64: c.slli gp, 53
+0xDA 0x11 # BAD32: invalid instruction encoding
+0xDA 0x11 # GOOD64: c.slli gp, 54
+0xDE 0x11 # BAD32: invalid instruction encoding
+0xDE 0x11 # GOOD64: c.s...
[truncated]

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llvmbot commented Mar 31, 2025

@llvm/pr-subscribers-mc

Author: Paul Bowen-Huggett (paulhuggett)

Changes

Fix for #133712.

The change causes c.slli instructions whose immediate has bit 5 to be rejected when disassembling RV32C. Added a test to exhaustively cover c.slli for 32 and bit targets. Minor tweak to make the debug output a little more readable.

Patch is 122.02 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/133713.diff

2 Files Affected:

  • (modified) llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp (+8-4)
  • (added) llvm/test/MC/Disassembler/RISCV/c_slli.txt (+3119)
diff --git a/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp b/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
index b46b72b4b73e9..b22a4a7246c23 100644
--- a/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
+++ b/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
@@ -558,8 +558,12 @@ static DecodeStatus decodeRVCInstrRdRs1UImm(MCInst &Inst, uint32_t Insn,
                                             const MCDisassembler *Decoder) {
   Inst.addOperand(MCOperand::createReg(RISCV::X0));
   Inst.addOperand(Inst.getOperand(0));
-  uint32_t UImm6 =
-      fieldFromInstruction(Insn, 12, 1) << 5 | fieldFromInstruction(Insn, 2, 5);
+
+  uint32_t UImm6 = fieldFromInstruction(Insn, 12, 1) << 5;
+  // On RV32C, uimm[5]=1 is reserved for custom extensions.
+  if (UImm6 != 0 && Decoder->getSubtargetInfo().hasFeature(RISCV::Feature32Bit))
+    return MCDisassembler::Fail;
+  UImm6 |= fieldFromInstruction(Insn, 2, 5);
   [[maybe_unused]] DecodeStatus Result =
       decodeUImmOperand<6>(Inst, UImm6, Address, Decoder);
   assert(Result == MCDisassembler::Success && "Invalid immediate");
@@ -784,7 +788,7 @@ DecodeStatus RISCVDisassembler::getInstruction16(MCInst &MI, uint64_t &Size,
     if (!Entry.haveContainedFeatures(STI.getFeatureBits()))
       continue;
 
-    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << "table:\n");
+    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << " table:\n");
     DecodeStatus Result =
         decodeInstruction(Entry.Table, MI, Insn, Address, this, STI);
     if (Result == MCDisassembler::Fail)
@@ -820,7 +824,7 @@ DecodeStatus RISCVDisassembler::getInstruction48(MCInst &MI, uint64_t &Size,
     if (!Entry.haveContainedFeatures(STI.getFeatureBits()))
       continue;
 
-    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << "table:\n");
+    LLVM_DEBUG(dbgs() << "Trying " << Entry.Desc << " table:\n");
     DecodeStatus Result =
         decodeInstruction(Entry.Table, MI, Insn, Address, this, STI);
     if (Result == MCDisassembler::Fail)
diff --git a/llvm/test/MC/Disassembler/RISCV/c_slli.txt b/llvm/test/MC/Disassembler/RISCV/c_slli.txt
new file mode 100644
index 0000000000000..6e8dc4c05147f
--- /dev/null
+++ b/llvm/test/MC/Disassembler/RISCV/c_slli.txt
@@ -0,0 +1,3119 @@
+# This test verifies the disassembler's behavior for all C.LUI opcodes with the
+# exception of those assigned to C.ADDI16SP
+#
+# RUN: llvm-mc --disassemble -triple=riscv32 -mattr=+c -M no-aliases \
+# RUN:     --show-encoding < %s | FileCheck --check-prefixes=GOOD %s
+#
+# RUN: llvm-mc --disassemble -triple=riscv64 -mattr=+c -M no-aliases \
+# RUN:     --show-encoding < %s | FileCheck --check-prefixes=GOOD,GOOD64 %s
+#
+# RUN: llvm-mc --disassemble -triple=riscv32 -mattr=+c -M no-aliases \
+# RUN:     --show-encoding < %s 2>&1 | FileCheck --check-prefix=BAD32 %s
+#
+# RUN: llvm-mc --disassemble -triple=riscv32  -mattr=+c -mattr=+no-rvc-hints \
+# RUN:     -M no-aliases --show-encoding < %s 2>&1 | \
+# RUN:   FileCheck --check-prefix=NOHINTS %s
+
+0x06 0x00 # GOOD: c.slli zero, 1
+0x06 0x00 # NOHINTS: invalid instruction encoding
+0x0A 0x00 # GOOD: c.slli zero, 2
+0x0A 0x00 # NOHINTS: invalid instruction encoding
+0x0E 0x00 # GOOD: c.slli zero, 3
+0x0E 0x00 # NOHINTS: invalid instruction encoding
+0x12 0x00 # GOOD: c.slli zero, 4
+0x12 0x00 # NOHINTS: invalid instruction encoding
+0x16 0x00 # GOOD: c.slli zero, 5
+0x16 0x00 # NOHINTS: invalid instruction encoding
+0x1A 0x00 # GOOD: c.slli zero, 6
+0x1A 0x00 # NOHINTS: invalid instruction encoding
+0x1E 0x00 # GOOD: c.slli zero, 7
+0x1E 0x00 # NOHINTS: invalid instruction encoding
+0x22 0x00 # GOOD: c.slli zero, 8
+0x22 0x00 # NOHINTS: invalid instruction encoding
+0x26 0x00 # GOOD: c.slli zero, 9
+0x26 0x00 # NOHINTS: invalid instruction encoding
+0x2A 0x00 # GOOD: c.slli zero, 10
+0x2A 0x00 # NOHINTS: invalid instruction encoding
+0x2E 0x00 # GOOD: c.slli zero, 11
+0x2E 0x00 # NOHINTS: invalid instruction encoding
+0x32 0x00 # GOOD: c.slli zero, 12
+0x32 0x00 # NOHINTS: invalid instruction encoding
+0x36 0x00 # GOOD: c.slli zero, 13
+0x36 0x00 # NOHINTS: invalid instruction encoding
+0x3A 0x00 # GOOD: c.slli zero, 14
+0x3A 0x00 # NOHINTS: invalid instruction encoding
+0x3E 0x00 # GOOD: c.slli zero, 15
+0x3E 0x00 # NOHINTS: invalid instruction encoding
+0x42 0x00 # GOOD: c.slli zero, 16
+0x42 0x00 # NOHINTS: invalid instruction encoding
+0x46 0x00 # GOOD: c.slli zero, 17
+0x46 0x00 # NOHINTS: invalid instruction encoding
+0x4A 0x00 # GOOD: c.slli zero, 18
+0x4A 0x00 # NOHINTS: invalid instruction encoding
+0x4E 0x00 # GOOD: c.slli zero, 19
+0x4E 0x00 # NOHINTS: invalid instruction encoding
+0x52 0x00 # GOOD: c.slli zero, 20
+0x52 0x00 # NOHINTS: invalid instruction encoding
+0x56 0x00 # GOOD: c.slli zero, 21
+0x56 0x00 # NOHINTS: invalid instruction encoding
+0x5A 0x00 # GOOD: c.slli zero, 22
+0x5A 0x00 # NOHINTS: invalid instruction encoding
+0x5E 0x00 # GOOD: c.slli zero, 23
+0x5E 0x00 # NOHINTS: invalid instruction encoding
+0x62 0x00 # GOOD: c.slli zero, 24
+0x62 0x00 # NOHINTS: invalid instruction encoding
+0x66 0x00 # GOOD: c.slli zero, 25
+0x66 0x00 # NOHINTS: invalid instruction encoding
+0x6A 0x00 # GOOD: c.slli zero, 26
+0x6A 0x00 # NOHINTS: invalid instruction encoding
+0x6E 0x00 # GOOD: c.slli zero, 27
+0x6E 0x00 # NOHINTS: invalid instruction encoding
+0x72 0x00 # GOOD: c.slli zero, 28
+0x72 0x00 # NOHINTS: invalid instruction encoding
+0x76 0x00 # GOOD: c.slli zero, 29
+0x76 0x00 # NOHINTS: invalid instruction encoding
+0x7A 0x00 # GOOD: c.slli zero, 30
+0x7A 0x00 # NOHINTS: invalid instruction encoding
+0x7E 0x00 # GOOD: c.slli zero, 31
+0x7E 0x00 # NOHINTS: invalid instruction encoding
+0x02 0x10 # BAD32: invalid instruction encoding
+0x02 0x10 # GOOD64: c.slli zero, 32
+0x02 0x10 # NOHINTS: invalid instruction encoding
+0x06 0x10 # BAD32: invalid instruction encoding
+0x06 0x10 # GOOD64: c.slli zero, 33
+0x06 0x10 # NOHINTS: invalid instruction encoding
+0x0A 0x10 # BAD32: invalid instruction encoding
+0x0A 0x10 # GOOD64: c.slli zero, 34
+0x0A 0x10 # NOHINTS: invalid instruction encoding
+0x0E 0x10 # BAD32: invalid instruction encoding
+0x0E 0x10 # GOOD64: c.slli zero, 35
+0x0E 0x10 # NOHINTS: invalid instruction encoding
+0x12 0x10 # BAD32: invalid instruction encoding
+0x12 0x10 # GOOD64: c.slli zero, 36
+0x12 0x10 # NOHINTS: invalid instruction encoding
+0x16 0x10 # BAD32: invalid instruction encoding
+0x16 0x10 # GOOD64: c.slli zero, 37
+0x16 0x10 # NOHINTS: invalid instruction encoding
+0x1A 0x10 # BAD32: invalid instruction encoding
+0x1A 0x10 # GOOD64: c.slli zero, 38
+0x1A 0x10 # NOHINTS: invalid instruction encoding
+0x1E 0x10 # BAD32: invalid instruction encoding
+0x1E 0x10 # GOOD64: c.slli zero, 39
+0x1E 0x10 # NOHINTS: invalid instruction encoding
+0x22 0x10 # BAD32: invalid instruction encoding
+0x22 0x10 # GOOD64: c.slli zero, 40
+0x22 0x10 # NOHINTS: invalid instruction encoding
+0x26 0x10 # BAD32: invalid instruction encoding
+0x26 0x10 # GOOD64: c.slli zero, 41
+0x26 0x10 # NOHINTS: invalid instruction encoding
+0x2A 0x10 # BAD32: invalid instruction encoding
+0x2A 0x10 # GOOD64: c.slli zero, 42
+0x2A 0x10 # NOHINTS: invalid instruction encoding
+0x2E 0x10 # BAD32: invalid instruction encoding
+0x2E 0x10 # GOOD64: c.slli zero, 43
+0x2E 0x10 # NOHINTS: invalid instruction encoding
+0x32 0x10 # BAD32: invalid instruction encoding
+0x32 0x10 # GOOD64: c.slli zero, 44
+0x32 0x10 # NOHINTS: invalid instruction encoding
+0x36 0x10 # BAD32: invalid instruction encoding
+0x36 0x10 # GOOD64: c.slli zero, 45
+0x36 0x10 # NOHINTS: invalid instruction encoding
+0x3A 0x10 # BAD32: invalid instruction encoding
+0x3A 0x10 # GOOD64: c.slli zero, 46
+0x3A 0x10 # NOHINTS: invalid instruction encoding
+0x3E 0x10 # BAD32: invalid instruction encoding
+0x3E 0x10 # GOOD64: c.slli zero, 47
+0x3E 0x10 # NOHINTS: invalid instruction encoding
+0x42 0x10 # BAD32: invalid instruction encoding
+0x42 0x10 # GOOD64: c.slli zero, 48
+0x42 0x10 # NOHINTS: invalid instruction encoding
+0x46 0x10 # BAD32: invalid instruction encoding
+0x46 0x10 # GOOD64: c.slli zero, 49
+0x46 0x10 # NOHINTS: invalid instruction encoding
+0x4A 0x10 # BAD32: invalid instruction encoding
+0x4A 0x10 # GOOD64: c.slli zero, 50
+0x4A 0x10 # NOHINTS: invalid instruction encoding
+0x4E 0x10 # BAD32: invalid instruction encoding
+0x4E 0x10 # GOOD64: c.slli zero, 51
+0x4E 0x10 # NOHINTS: invalid instruction encoding
+0x52 0x10 # BAD32: invalid instruction encoding
+0x52 0x10 # GOOD64: c.slli zero, 52
+0x52 0x10 # NOHINTS: invalid instruction encoding
+0x56 0x10 # BAD32: invalid instruction encoding
+0x56 0x10 # GOOD64: c.slli zero, 53
+0x56 0x10 # NOHINTS: invalid instruction encoding
+0x5A 0x10 # BAD32: invalid instruction encoding
+0x5A 0x10 # GOOD64: c.slli zero, 54
+0x5A 0x10 # NOHINTS: invalid instruction encoding
+0x5E 0x10 # BAD32: invalid instruction encoding
+0x5E 0x10 # GOOD64: c.slli zero, 55
+0x5E 0x10 # NOHINTS: invalid instruction encoding
+0x62 0x10 # BAD32: invalid instruction encoding
+0x62 0x10 # GOOD64: c.slli zero, 56
+0x62 0x10 # NOHINTS: invalid instruction encoding
+0x66 0x10 # BAD32: invalid instruction encoding
+0x66 0x10 # GOOD64: c.slli zero, 57
+0x66 0x10 # NOHINTS: invalid instruction encoding
+0x6A 0x10 # BAD32: invalid instruction encoding
+0x6A 0x10 # GOOD64: c.slli zero, 58
+0x6A 0x10 # NOHINTS: invalid instruction encoding
+0x6E 0x10 # BAD32: invalid instruction encoding
+0x6E 0x10 # GOOD64: c.slli zero, 59
+0x6E 0x10 # NOHINTS: invalid instruction encoding
+0x72 0x10 # BAD32: invalid instruction encoding
+0x72 0x10 # GOOD64: c.slli zero, 60
+0x72 0x10 # NOHINTS: invalid instruction encoding
+0x76 0x10 # BAD32: invalid instruction encoding
+0x76 0x10 # GOOD64: c.slli zero, 61
+0x76 0x10 # NOHINTS: invalid instruction encoding
+0x7A 0x10 # BAD32: invalid instruction encoding
+0x7A 0x10 # GOOD64: c.slli zero, 62
+0x7A 0x10 # NOHINTS: invalid instruction encoding
+0x7E 0x10 # BAD32: invalid instruction encoding
+0x7E 0x10 # GOOD64: c.slli zero, 63
+0x7E 0x10 # NOHINTS: invalid instruction encoding
+0x86 0x00 # GOOD: c.slli ra, 1
+0x8A 0x00 # GOOD: c.slli ra, 2
+0x8E 0x00 # GOOD: c.slli ra, 3
+0x92 0x00 # GOOD: c.slli ra, 4
+0x96 0x00 # GOOD: c.slli ra, 5
+0x9A 0x00 # GOOD: c.slli ra, 6
+0x9E 0x00 # GOOD: c.slli ra, 7
+0xA2 0x00 # GOOD: c.slli ra, 8
+0xA6 0x00 # GOOD: c.slli ra, 9
+0xAA 0x00 # GOOD: c.slli ra, 10
+0xAE 0x00 # GOOD: c.slli ra, 11
+0xB2 0x00 # GOOD: c.slli ra, 12
+0xB6 0x00 # GOOD: c.slli ra, 13
+0xBA 0x00 # GOOD: c.slli ra, 14
+0xBE 0x00 # GOOD: c.slli ra, 15
+0xC2 0x00 # GOOD: c.slli ra, 16
+0xC6 0x00 # GOOD: c.slli ra, 17
+0xCA 0x00 # GOOD: c.slli ra, 18
+0xCE 0x00 # GOOD: c.slli ra, 19
+0xD2 0x00 # GOOD: c.slli ra, 20
+0xD6 0x00 # GOOD: c.slli ra, 21
+0xDA 0x00 # GOOD: c.slli ra, 22
+0xDE 0x00 # GOOD: c.slli ra, 23
+0xE2 0x00 # GOOD: c.slli ra, 24
+0xE6 0x00 # GOOD: c.slli ra, 25
+0xEA 0x00 # GOOD: c.slli ra, 26
+0xEE 0x00 # GOOD: c.slli ra, 27
+0xF2 0x00 # GOOD: c.slli ra, 28
+0xF6 0x00 # GOOD: c.slli ra, 29
+0xFA 0x00 # GOOD: c.slli ra, 30
+0xFE 0x00 # GOOD: c.slli ra, 31
+0x82 0x10 # BAD32: invalid instruction encoding
+0x82 0x10 # GOOD64: c.slli ra, 32
+0x86 0x10 # BAD32: invalid instruction encoding
+0x86 0x10 # GOOD64: c.slli ra, 33
+0x8A 0x10 # BAD32: invalid instruction encoding
+0x8A 0x10 # GOOD64: c.slli ra, 34
+0x8E 0x10 # BAD32: invalid instruction encoding
+0x8E 0x10 # GOOD64: c.slli ra, 35
+0x92 0x10 # BAD32: invalid instruction encoding
+0x92 0x10 # GOOD64: c.slli ra, 36
+0x96 0x10 # BAD32: invalid instruction encoding
+0x96 0x10 # GOOD64: c.slli ra, 37
+0x9A 0x10 # BAD32: invalid instruction encoding
+0x9A 0x10 # GOOD64: c.slli ra, 38
+0x9E 0x10 # BAD32: invalid instruction encoding
+0x9E 0x10 # GOOD64: c.slli ra, 39
+0xA2 0x10 # BAD32: invalid instruction encoding
+0xA2 0x10 # GOOD64: c.slli ra, 40
+0xA6 0x10 # BAD32: invalid instruction encoding
+0xA6 0x10 # GOOD64: c.slli ra, 41
+0xAA 0x10 # BAD32: invalid instruction encoding
+0xAA 0x10 # GOOD64: c.slli ra, 42
+0xAE 0x10 # BAD32: invalid instruction encoding
+0xAE 0x10 # GOOD64: c.slli ra, 43
+0xB2 0x10 # BAD32: invalid instruction encoding
+0xB2 0x10 # GOOD64: c.slli ra, 44
+0xB6 0x10 # BAD32: invalid instruction encoding
+0xB6 0x10 # GOOD64: c.slli ra, 45
+0xBA 0x10 # BAD32: invalid instruction encoding
+0xBA 0x10 # GOOD64: c.slli ra, 46
+0xBE 0x10 # BAD32: invalid instruction encoding
+0xBE 0x10 # GOOD64: c.slli ra, 47
+0xC2 0x10 # BAD32: invalid instruction encoding
+0xC2 0x10 # GOOD64: c.slli ra, 48
+0xC6 0x10 # BAD32: invalid instruction encoding
+0xC6 0x10 # GOOD64: c.slli ra, 49
+0xCA 0x10 # BAD32: invalid instruction encoding
+0xCA 0x10 # GOOD64: c.slli ra, 50
+0xCE 0x10 # BAD32: invalid instruction encoding
+0xCE 0x10 # GOOD64: c.slli ra, 51
+0xD2 0x10 # BAD32: invalid instruction encoding
+0xD2 0x10 # GOOD64: c.slli ra, 52
+0xD6 0x10 # BAD32: invalid instruction encoding
+0xD6 0x10 # GOOD64: c.slli ra, 53
+0xDA 0x10 # BAD32: invalid instruction encoding
+0xDA 0x10 # GOOD64: c.slli ra, 54
+0xDE 0x10 # BAD32: invalid instruction encoding
+0xDE 0x10 # GOOD64: c.slli ra, 55
+0xE2 0x10 # BAD32: invalid instruction encoding
+0xE2 0x10 # GOOD64: c.slli ra, 56
+0xE6 0x10 # BAD32: invalid instruction encoding
+0xE6 0x10 # GOOD64: c.slli ra, 57
+0xEA 0x10 # BAD32: invalid instruction encoding
+0xEA 0x10 # GOOD64: c.slli ra, 58
+0xEE 0x10 # BAD32: invalid instruction encoding
+0xEE 0x10 # GOOD64: c.slli ra, 59
+0xF2 0x10 # BAD32: invalid instruction encoding
+0xF2 0x10 # GOOD64: c.slli ra, 60
+0xF6 0x10 # BAD32: invalid instruction encoding
+0xF6 0x10 # GOOD64: c.slli ra, 61
+0xFA 0x10 # BAD32: invalid instruction encoding
+0xFA 0x10 # GOOD64: c.slli ra, 62
+0xFE 0x10 # BAD32: invalid instruction encoding
+0xFE 0x10 # GOOD64: c.slli ra, 63
+0x06 0x01 # GOOD: c.slli sp, 1
+0x0A 0x01 # GOOD: c.slli sp, 2
+0x0E 0x01 # GOOD: c.slli sp, 3
+0x12 0x01 # GOOD: c.slli sp, 4
+0x16 0x01 # GOOD: c.slli sp, 5
+0x1A 0x01 # GOOD: c.slli sp, 6
+0x1E 0x01 # GOOD: c.slli sp, 7
+0x22 0x01 # GOOD: c.slli sp, 8
+0x26 0x01 # GOOD: c.slli sp, 9
+0x2A 0x01 # GOOD: c.slli sp, 10
+0x2E 0x01 # GOOD: c.slli sp, 11
+0x32 0x01 # GOOD: c.slli sp, 12
+0x36 0x01 # GOOD: c.slli sp, 13
+0x3A 0x01 # GOOD: c.slli sp, 14
+0x3E 0x01 # GOOD: c.slli sp, 15
+0x42 0x01 # GOOD: c.slli sp, 16
+0x46 0x01 # GOOD: c.slli sp, 17
+0x4A 0x01 # GOOD: c.slli sp, 18
+0x4E 0x01 # GOOD: c.slli sp, 19
+0x52 0x01 # GOOD: c.slli sp, 20
+0x56 0x01 # GOOD: c.slli sp, 21
+0x5A 0x01 # GOOD: c.slli sp, 22
+0x5E 0x01 # GOOD: c.slli sp, 23
+0x62 0x01 # GOOD: c.slli sp, 24
+0x66 0x01 # GOOD: c.slli sp, 25
+0x6A 0x01 # GOOD: c.slli sp, 26
+0x6E 0x01 # GOOD: c.slli sp, 27
+0x72 0x01 # GOOD: c.slli sp, 28
+0x76 0x01 # GOOD: c.slli sp, 29
+0x7A 0x01 # GOOD: c.slli sp, 30
+0x7E 0x01 # GOOD: c.slli sp, 31
+0x02 0x11 # BAD32: invalid instruction encoding
+0x02 0x11 # GOOD64: c.slli sp, 32
+0x06 0x11 # BAD32: invalid instruction encoding
+0x06 0x11 # GOOD64: c.slli sp, 33
+0x0A 0x11 # BAD32: invalid instruction encoding
+0x0A 0x11 # GOOD64: c.slli sp, 34
+0x0E 0x11 # BAD32: invalid instruction encoding
+0x0E 0x11 # GOOD64: c.slli sp, 35
+0x12 0x11 # BAD32: invalid instruction encoding
+0x12 0x11 # GOOD64: c.slli sp, 36
+0x16 0x11 # BAD32: invalid instruction encoding
+0x16 0x11 # GOOD64: c.slli sp, 37
+0x1A 0x11 # BAD32: invalid instruction encoding
+0x1A 0x11 # GOOD64: c.slli sp, 38
+0x1E 0x11 # BAD32: invalid instruction encoding
+0x1E 0x11 # GOOD64: c.slli sp, 39
+0x22 0x11 # BAD32: invalid instruction encoding
+0x22 0x11 # GOOD64: c.slli sp, 40
+0x26 0x11 # BAD32: invalid instruction encoding
+0x26 0x11 # GOOD64: c.slli sp, 41
+0x2A 0x11 # BAD32: invalid instruction encoding
+0x2A 0x11 # GOOD64: c.slli sp, 42
+0x2E 0x11 # BAD32: invalid instruction encoding
+0x2E 0x11 # GOOD64: c.slli sp, 43
+0x32 0x11 # BAD32: invalid instruction encoding
+0x32 0x11 # GOOD64: c.slli sp, 44
+0x36 0x11 # BAD32: invalid instruction encoding
+0x36 0x11 # GOOD64: c.slli sp, 45
+0x3A 0x11 # BAD32: invalid instruction encoding
+0x3A 0x11 # GOOD64: c.slli sp, 46
+0x3E 0x11 # BAD32: invalid instruction encoding
+0x3E 0x11 # GOOD64: c.slli sp, 47
+0x42 0x11 # BAD32: invalid instruction encoding
+0x42 0x11 # GOOD64: c.slli sp, 48
+0x46 0x11 # BAD32: invalid instruction encoding
+0x46 0x11 # GOOD64: c.slli sp, 49
+0x4A 0x11 # BAD32: invalid instruction encoding
+0x4A 0x11 # GOOD64: c.slli sp, 50
+0x4E 0x11 # BAD32: invalid instruction encoding
+0x4E 0x11 # GOOD64: c.slli sp, 51
+0x52 0x11 # BAD32: invalid instruction encoding
+0x52 0x11 # GOOD64: c.slli sp, 52
+0x56 0x11 # BAD32: invalid instruction encoding
+0x56 0x11 # GOOD64: c.slli sp, 53
+0x5A 0x11 # BAD32: invalid instruction encoding
+0x5A 0x11 # GOOD64: c.slli sp, 54
+0x5E 0x11 # BAD32: invalid instruction encoding
+0x5E 0x11 # GOOD64: c.slli sp, 55
+0x62 0x11 # BAD32: invalid instruction encoding
+0x62 0x11 # GOOD64: c.slli sp, 56
+0x66 0x11 # BAD32: invalid instruction encoding
+0x66 0x11 # GOOD64: c.slli sp, 57
+0x6A 0x11 # BAD32: invalid instruction encoding
+0x6A 0x11 # GOOD64: c.slli sp, 58
+0x6E 0x11 # BAD32: invalid instruction encoding
+0x6E 0x11 # GOOD64: c.slli sp, 59
+0x72 0x11 # BAD32: invalid instruction encoding
+0x72 0x11 # GOOD64: c.slli sp, 60
+0x76 0x11 # BAD32: invalid instruction encoding
+0x76 0x11 # GOOD64: c.slli sp, 61
+0x7A 0x11 # BAD32: invalid instruction encoding
+0x7A 0x11 # GOOD64: c.slli sp, 62
+0x7E 0x11 # BAD32: invalid instruction encoding
+0x7E 0x11 # GOOD64: c.slli sp, 63
+0x86 0x01 # GOOD: c.slli gp, 1
+0x8A 0x01 # GOOD: c.slli gp, 2
+0x8E 0x01 # GOOD: c.slli gp, 3
+0x92 0x01 # GOOD: c.slli gp, 4
+0x96 0x01 # GOOD: c.slli gp, 5
+0x9A 0x01 # GOOD: c.slli gp, 6
+0x9E 0x01 # GOOD: c.slli gp, 7
+0xA2 0x01 # GOOD: c.slli gp, 8
+0xA6 0x01 # GOOD: c.slli gp, 9
+0xAA 0x01 # GOOD: c.slli gp, 10
+0xAE 0x01 # GOOD: c.slli gp, 11
+0xB2 0x01 # GOOD: c.slli gp, 12
+0xB6 0x01 # GOOD: c.slli gp, 13
+0xBA 0x01 # GOOD: c.slli gp, 14
+0xBE 0x01 # GOOD: c.slli gp, 15
+0xC2 0x01 # GOOD: c.slli gp, 16
+0xC6 0x01 # GOOD: c.slli gp, 17
+0xCA 0x01 # GOOD: c.slli gp, 18
+0xCE 0x01 # GOOD: c.slli gp, 19
+0xD2 0x01 # GOOD: c.slli gp, 20
+0xD6 0x01 # GOOD: c.slli gp, 21
+0xDA 0x01 # GOOD: c.slli gp, 22
+0xDE 0x01 # GOOD: c.slli gp, 23
+0xE2 0x01 # GOOD: c.slli gp, 24
+0xE6 0x01 # GOOD: c.slli gp, 25
+0xEA 0x01 # GOOD: c.slli gp, 26
+0xEE 0x01 # GOOD: c.slli gp, 27
+0xF2 0x01 # GOOD: c.slli gp, 28
+0xF6 0x01 # GOOD: c.slli gp, 29
+0xFA 0x01 # GOOD: c.slli gp, 30
+0xFE 0x01 # GOOD: c.slli gp, 31
+0x82 0x11 # BAD32: invalid instruction encoding
+0x82 0x11 # GOOD64: c.slli gp, 32
+0x86 0x11 # BAD32: invalid instruction encoding
+0x86 0x11 # GOOD64: c.slli gp, 33
+0x8A 0x11 # BAD32: invalid instruction encoding
+0x8A 0x11 # GOOD64: c.slli gp, 34
+0x8E 0x11 # BAD32: invalid instruction encoding
+0x8E 0x11 # GOOD64: c.slli gp, 35
+0x92 0x11 # BAD32: invalid instruction encoding
+0x92 0x11 # GOOD64: c.slli gp, 36
+0x96 0x11 # BAD32: invalid instruction encoding
+0x96 0x11 # GOOD64: c.slli gp, 37
+0x9A 0x11 # BAD32: invalid instruction encoding
+0x9A 0x11 # GOOD64: c.slli gp, 38
+0x9E 0x11 # BAD32: invalid instruction encoding
+0x9E 0x11 # GOOD64: c.slli gp, 39
+0xA2 0x11 # BAD32: invalid instruction encoding
+0xA2 0x11 # GOOD64: c.slli gp, 40
+0xA6 0x11 # BAD32: invalid instruction encoding
+0xA6 0x11 # GOOD64: c.slli gp, 41
+0xAA 0x11 # BAD32: invalid instruction encoding
+0xAA 0x11 # GOOD64: c.slli gp, 42
+0xAE 0x11 # BAD32: invalid instruction encoding
+0xAE 0x11 # GOOD64: c.slli gp, 43
+0xB2 0x11 # BAD32: invalid instruction encoding
+0xB2 0x11 # GOOD64: c.slli gp, 44
+0xB6 0x11 # BAD32: invalid instruction encoding
+0xB6 0x11 # GOOD64: c.slli gp, 45
+0xBA 0x11 # BAD32: invalid instruction encoding
+0xBA 0x11 # GOOD64: c.slli gp, 46
+0xBE 0x11 # BAD32: invalid instruction encoding
+0xBE 0x11 # GOOD64: c.slli gp, 47
+0xC2 0x11 # BAD32: invalid instruction encoding
+0xC2 0x11 # GOOD64: c.slli gp, 48
+0xC6 0x11 # BAD32: invalid instruction encoding
+0xC6 0x11 # GOOD64: c.slli gp, 49
+0xCA 0x11 # BAD32: invalid instruction encoding
+0xCA 0x11 # GOOD64: c.slli gp, 50
+0xCE 0x11 # BAD32: invalid instruction encoding
+0xCE 0x11 # GOOD64: c.slli gp, 51
+0xD2 0x11 # BAD32: invalid instruction encoding
+0xD2 0x11 # GOOD64: c.slli gp, 52
+0xD6 0x11 # BAD32: invalid instruction encoding
+0xD6 0x11 # GOOD64: c.slli gp, 53
+0xDA 0x11 # BAD32: invalid instruction encoding
+0xDA 0x11 # GOOD64: c.slli gp, 54
+0xDE 0x11 # BAD32: invalid instruction encoding
+0xDE 0x11 # GOOD64: c.s...
[truncated]

topperc
topperc approved these changes Mar 31, 2025
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LGTM

@paulhuggett
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Thank you both. Assuming you're happy and don't expect the "Linux Premerge Checks" check to start any time soon, would you be kind enough to merge it for me, please?

@topperc topperc merged commit ea06f7f into llvm:main Mar 31, 2025
13 of 14 checks passed
@paulhuggett paulhuggett deleted the c_slli_1006 branch March 31, 2025 15:56
topperc
topperc reviewed Mar 31, 2025
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llvm/test/MC/Disassembler/RISCV/c_slli.txt
# RUN: -M no-aliases --show-encoding < %s 2>&1 | \
# RUN: FileCheck --check-prefix=NOHINTS %s

0x06 0x00 # GOOD: c.slli zero, 1
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This test is actually buggy. Each hex pattern should only appear once. All 4 command lines will process each hex value not just the ones with their check-prefix.

So the total number of "invalid instruction encoding" that appear in the output is more than how many we are checking for. The same bug is in the c.lui test and it's causing us to miss that we incorrectly decode 'c.lui zero, 0'.

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Thanks for letting me know. I'll fix it and post a new PR.

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(PR #133921)

@paulhuggett paulhuggett mentioned this pull request Apr 1, 2025
Merged
topperc pushed a commit that referenced this pull request Apr 1, 2025
@paulhuggett
[RISCV] Fix the c_slli disassembler test (NFC) (#133921)
75242a8 
This change fixes the exhaustive text for the c.slli instruction so that
each hex pattern now appears only once. The problem was spotted
[here](#133713 (comment))
by @topperc (for which, thank you).
llvm-sync bot pushed a commit to arm/arm-toolchain that referenced this pull request Apr 1, 2025
@paulhuggett @github-actions
Automerge: [RISCV] Fix the c_slli disassembler test (NFC) (#133921)
0b0a73a 
This change fixes the exhaustive text for the c.slli instruction so that
each hex pattern now appears only once. The problem was spotted
[here](llvm/llvm-project#133713 (comment))
by @topperc (for which, thank you).
Ankur-0429 pushed a commit to Ankur-0429/llvm-project that referenced this pull request Apr 2, 2025
@paulhuggett @Ankur-0429
[RISCV] Fix the c_slli disassembler test (NFC) (llvm#133921)
90683d7 
This change fixes the exhaustive text for the c.slli instruction so that
each hex pattern now appears only once. The problem was spotted
[here](llvm#133713 (comment))
by @topperc (for which, thank you).
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@topperc topperc topperc approved these changes

@lenary lenary lenary approved these changes

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@paulhuggett @llvmbot @lenary @topperc