From 79c163d6ddeb84ea1743eca0644688951bfc5a97 Mon Sep 17 00:00:00 2001 From: Tilmann Scheller Date: Wed, 3 Jul 2013 20:38:01 +0000 Subject: ARM: Prevent ARMAsmParser::shouldOmitCCOutOperand() from misidentifying certain Thumb2 add immediate T3 encodings. Before the fix Thumb2 instructions of type "add rD, rN, #imm" (T3 encoding, see ARM ARM A8.8.4) with rD and rN both being low registers (r0-r7) were classified as having the T4 encoding. The T4 encoding doesn't have a cc_out operand so for above instructions the operand gets erroneously removed, corrupting the token stream and leading to parse errors later in the process. This bug prevented "add r1, r7, #0xcbcbcbcb" from being assembled correctly. Fixes . git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185575 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/AsmParser/ARMAsmParser.cpp | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) (limited to 'lib/Target/ARM') diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp index c270ed0..bd4ea53 100644 --- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp +++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp @@ -5076,15 +5076,6 @@ bool ARMAsmParser::shouldOmitCCOutOperand(StringRef Mnemonic, static_cast(Operands[5])->isImm()) { // Nest conditions rather than one big 'if' statement for readability. // - // If either register is a high reg, it's either one of the SP - // variants (handled above) or a 32-bit encoding, so we just - // check against T3. If the second register is the PC, this is an - // alternate form of ADR, which uses encoding T4, so check for that too. - if ((!isARMLowRegister(static_cast(Operands[3])->getReg()) || - !isARMLowRegister(static_cast(Operands[4])->getReg())) && - static_cast(Operands[4])->getReg() != ARM::PC && - static_cast(Operands[5])->isT2SOImm()) - return false; // If both registers are low, we're in an IT block, and the immediate is // in range, we should use encoding T1 instead, which has a cc_out. if (inITBlock() && @@ -5092,6 +5083,11 @@ bool ARMAsmParser::shouldOmitCCOutOperand(StringRef Mnemonic, isARMLowRegister(static_cast(Operands[4])->getReg()) && static_cast(Operands[5])->isImm0_7()) return false; + // Check against T3. If the second register is the PC, this is an + // alternate form of ADR, which uses encoding T4, so check for that too. + if (static_cast(Operands[4])->getReg() != ARM::PC && + static_cast(Operands[5])->isT2SOImm()) + return false; // Otherwise, we use encoding T4, which does not have a cc_out // operand. -- cgit v1.1