[Mips] Fix clang crashes when assembling invalid MIPS beql instructions with --arch=mips #156413
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@llvm/pr-subscribers-backend-mips Author: None (yingopq) ChangesFrom clang version 4, mips append new instruction BeqImm and BEQLImmMacro, the second operand of instruction format is imm64:$imm. When Mips process Fix #151453. Full diff: https://github.com/llvm/llvm-project/pull/156413.diff 1 Files Affected:
diff --git a/llvm/lib/Target/Mips/MipsInstrInfo.td b/llvm/lib/Target/Mips/MipsInstrInfo.td
index a124e84e9ca5f..0d6fa25fb8025 100644
--- a/llvm/lib/Target/Mips/MipsInstrInfo.td
+++ b/llvm/lib/Target/Mips/MipsInstrInfo.td
@@ -855,7 +855,15 @@ def calltarget : Operand<iPTR> {
let PrintMethod = "printJumpOperand";
}
-def imm64: Operand<i64>;
+def ConstantImmAsmOperandClass : AsmOperandClass {
+ let Name = "ConstantImm";
+ let PredicateMethod = "isConstantImm";
+ let RenderMethod = "addImmOperands";
+}
+
+def imm64: Operand<i64> {
+ let ParserMatchClass = ConstantImmAsmOperandClass;
+}
def simm19_lsl2 : Operand<i32> {
let EncoderMethod = "getSimm19Lsl2Encoding";
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@arsenm Can you help review this pr? This issue has been tested OK in the comments section of the issue. |
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| # RUN: not llvm-mc %s -triple=mips -mcpu=mips32 2>&1 | FileCheck %s | ||
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| # CHECK: error: invalid operand for instruction | ||
| beql $t0, ($t0), 1 |
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This changed at least 2 opcodes, right? Should test all of them (missing bne?)
…ns with --arch=mips From clang version 4, mips append new instruction BeqImm and BEQLImm, the second operand format of instruction is imm64:$imm. 1.When Mips process `beql $t0, ($t0), 1`, it think the second operand was an imm, so match success. Then mips backend process expandBranchImm, check the second operand `$t0` was not imm, reported asserts. We can strengthen the second operand matching restrictions. 2.Similarly, when Mips process `beql $t0, (1), 1`, it think the second was an imm. so match success. Then mips backend process expandBranchImm, check the third operand `1` was not expression, reported asserts. Permit the third operand of `beql` to be imm. Fix llvm#151453.
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From clang version 4, mips append new instruction BeqImm and BEQLImmMacro, the second operand of instruction format is imm64:$imm. When Mips process
beql $t0, ($t0), 1, it think the second operand was an imm, so match success. Then mips backend process expandBranchImm, check the Operand(1) was not imm, reported failure.We can strengthen the instruction matching restrictions.
Fixes #151453.