[RISCV][MC] Reject bare symbols for the simm6 and simm6nonzero operand types

Summary:
Fixed assertions due to invalid fixup when encoding compressed instructions
 (c.addi, c.addiw, c.li, c.andi) with bare symbols with/without modifiers.
  This matches GAS behavior as well.

This bug was uncovered by a LLVM MC Disassembler Protocol Buffer Fuzzer
for the RISC-V assembly language.

Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, asb

Differential Revision: https://reviews.llvm.org/D52005

llvm-svn: 342160

diff --git a/llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp b/llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp
index 3e469c8..7b010f5 100644 (file)
--- a/llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp
+++ b/llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp
@@ -326,14 +326,9 @@ public:
       return false;
     RISCVMCExpr::VariantKind VK;
     int64_t Imm;
-    bool IsValid;
     bool IsConstantImm = evaluateConstantImm(Imm, VK);
-    if (!IsConstantImm)
-      IsValid = RISCVAsmParser::classifySymbolRef(getImm(), VK, Imm);
-    else
-      IsValid = isInt<6>(Imm);
-    return IsValid &&
-           (VK == RISCVMCExpr::VK_RISCV_None || VK == RISCVMCExpr::VK_RISCV_LO);
+    return IsConstantImm && isInt<6>(Imm) &&
+           VK == RISCVMCExpr::VK_RISCV_None;
   }
 
   bool isSImm6NonZero() const {
@@ -341,14 +336,9 @@ public:
       return false;
     RISCVMCExpr::VariantKind VK;
     int64_t Imm;
-    bool IsValid;
     bool IsConstantImm = evaluateConstantImm(Imm, VK);
-    if (!IsConstantImm)
-      IsValid = RISCVAsmParser::classifySymbolRef(getImm(), VK, Imm);
-    else
-      IsValid = ((Imm != 0) && isInt<6>(Imm));
-    return IsValid &&
-           (VK == RISCVMCExpr::VK_RISCV_None || VK == RISCVMCExpr::VK_RISCV_LO);
+    return IsConstantImm && isInt<6>(Imm) && (Imm != 0) &&
+           VK == RISCVMCExpr::VK_RISCV_None;
   }
 
   bool isCLUIImm() const {

diff --git a/llvm/test/MC/RISCV/rv32c-invalid.s b/llvm/test/MC/RISCV/rv32c-invalid.s
index 8ee7c96..9981f67 100644 (file)
--- a/llvm/test/MC/RISCV/rv32c-invalid.s
+++ b/llvm/test/MC/RISCV/rv32c-invalid.s
@@ -45,12 +45,21 @@ c.srai a0, 0  # CHECK: :[[@LINE]]:12: error: immediate must be an integer in the
 
 ## simm6
 c.li t0, 128 # CHECK: :[[@LINE]]:10: error: immediate must be an integer in the range [-32, 31]
+c.li t0, foo # CHECK: :[[@LINE]]:10: error: immediate must be an integer in the range [-32, 31]
+c.li t0, %lo(foo) # CHECK: :[[@LINE]]:10: error: immediate must be an integer in the range [-32, 31]
+c.li t0, %hi(foo) # CHECK: :[[@LINE]]:10: error: immediate must be an integer in the range [-32, 31]
 c.andi a0, -33 # CHECK: :[[@LINE]]:12: error: immediate must be an integer in the range [-32, 31]
+c.andi a0, foo # CHECK: :[[@LINE]]:12: error: immediate must be an integer in the range [-32, 31]
+c.andi a0, %lo(foo) # CHECK: :[[@LINE]]:12: error: immediate must be an integer in the range [-32, 31]
+c.andi a0, %hi(foo) # CHECK: :[[@LINE]]:12: error: immediate must be an integer in the range [-32, 31]
 
 ## simm6nonzero
 c.addi t0, 0 # CHECK: :[[@LINE]]:12: error: immediate must be non-zero in the range [-32, 31]
 c.addi t0, -33 # CHECK: :[[@LINE]]:12: error: immediate must be non-zero in the range [-32, 31]
 c.addi t0, 32 # CHECK: :[[@LINE]]:12: error: immediate must be non-zero in the range [-32, 31]
+c.addi t0, foo # CHECK: :[[@LINE]]:12: error: immediate must be non-zero in the range [-32, 31]
+c.addi t0, %lo(foo) # CHECK: :[[@LINE]]:12: error: immediate must be non-zero in the range [-32, 31]
+c.addi t0, %hi(foo) # CHECK: :[[@LINE]]:12: error: immediate must be non-zero in the range [-32, 31]
 
 ## c_lui_imm
 c.lui t0, 0 # CHECK: :[[@LINE]]:11: error: immediate must be in [0xfffe0, 0xfffff] or [1, 31]

diff --git a/llvm/test/MC/RISCV/rv64c-invalid.s b/llvm/test/MC/RISCV/rv64c-invalid.s
index fdbcaba..e50f48b 100644 (file)
--- a/llvm/test/MC/RISCV/rv64c-invalid.s
+++ b/llvm/test/MC/RISCV/rv64c-invalid.s
@@ -20,6 +20,9 @@ c.srai a0, 0  # CHECK: :[[@LINE]]:12: error: immediate must be an integer in the
 ## simm6
 c.addiw t0, -33 # CHECK: :[[@LINE]]:13: error: immediate must be an integer in the range [-32, 31]
 c.addiw t0, 32 # CHECK: :[[@LINE]]:13: error: immediate must be an integer in the range [-32, 31]
+c.addiw t0, foo # CHECK: :[[@LINE]]:13: error: immediate must be an integer in the range [-32, 31]
+c.addiw t0, %lo(foo) # CHECK: :[[@LINE]]:13: error: immediate must be an integer in the range [-32, 31]
+c.addiw t0, %hi(foo) # CHECK: :[[@LINE]]:13: error: immediate must be an integer in the range [-32, 31]
 
 ## uimm9_lsb000
 c.ldsp  ra, 512(sp) # CHECK: :[[@LINE]]:13: error: immediate must be a multiple of 8 bytes in the range [0, 504]