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authorMaciej W. Rozycki <macro@imgtec.com>2016-12-23 16:49:42 +0000
committerMaciej W. Rozycki <macro@imgtec.com>2016-12-23 19:33:45 +0000
commit0674ee5dada21c8deec690ca66d5b2870f13ea49 (patch)
tree2db467165d33ec3a9d2fb87e5caa63f292513171 /include
parentb2805ed55456cea2694d31fc8627cca17120267b (diff)
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MIPS16: Handle non-extensible instructions correctly
Identify non-extensible instructions in the MIPS16 opcode table and disallow their use with the `.e' instruction size suffix in assembly and do not interpret any EXTEND prefix present as a part of the instruction in disassembly. According to all versions of the MIPS16 ASE specifications the following instructions encodings are not extensible [1][2][3][4][5][6]: I8/MOV32R, I8/MOVR32, all RRR minor opcodes, all RR minor opcodes except from DSRA and DSRL, and EXTEND itself, and as from revision 2.50 of the MIPS16e ASE specifications it has been further clarified what was previously implied, that non-extesiable instructions when preceded with an EXTEND prefix must cause a Reserved Instruction exception [3][5]. Therefore in the presence of an EXTEND prefix none of these instructions are supposed to be handled as extended instructions and supporting these forms in disassembly causes confusion, and in the case of the RRR major opcode it also clashes with the ASMACRO encoding. References: [1] "Product Description, MIPS16 Application-Specific Extension", Version 1.3, MIPS Technologies, Inc., 970130, Table 3. "MIPS16 Instruction Set Summary", p. 5 [2] same, Table 5 "RR Minor Opcodes (RR-type instructions)", p.10 [3] "MIPS32 Architecture for Programmers, Volume IV-a: The MIPS16e Application-Specific Extension to the MIPS32 Architecture", MIPS Technologies, Inc., Document Number: MD00076, Revision 2.63, July 16, 2013, Section 3.9 "MIPS16e Instruction Summaries", pp. 37-39 [4] same, Section 3.15 "Instruction Bit Encoding", pp. 46-49 [5] "MIPS64 Architecture for Programmers, Volume IV-a: The MIPS16e Application-Specific Extension to the MIPS64 Architecture", MIPS Technologies, Inc., Document Number: MD00077, Revision 2.60, June 25, 2008, Section 1.9 "MIPS16e Instruction Summaries", pp. 38-41 [6] same, Section 1.15 "Instruction Bit Encoding", pp. 48-51 include/ * opcode/mips.h (INSN2_SHORT_ONLY): New macro. gas/ * config/tc-mips.c (is_size_valid_16): Disallow a `.e' suffix instruction size override for INSN2_SHORT_ONLY opcode table entries. * testsuite/gas/mips/mips16-extend-swap.d: Adjust output. * testsuite/gas/mips/mips16-macro-e.l: Adjust error messages. * testsuite/gas/mips/mips16-32@mips16-macro-e.l: Adjust error messages. * testsuite/gas/mips/mips16e-32@mips16-macro-e.l: Adjust error messages. * testsuite/gas/mips/mips16-insn-e.d: New test. * testsuite/gas/mips/mips16-insn-t.d: New test. * testsuite/gas/mips/mips16-32@mips16-insn-e.d: New test. * testsuite/gas/mips/mips16-64@mips16-insn-e.d: New test. * testsuite/gas/mips/mips16e-32@mips16-insn-e.d: New test. * testsuite/gas/mips/mips16-32@mips16-insn-t.d: New test. * testsuite/gas/mips/mips16-64@mips16-insn-t.d: New test. * testsuite/gas/mips/mips16e-32@mips16-insn-t.d: New test. * testsuite/gas/mips/mips16-insn-e.l: New stderr output. * testsuite/gas/mips/mips16-insn-t.l: New stderr output. * testsuite/gas/mips/mips16-32@mips16-insn-e.l: New stderr output. * testsuite/gas/mips/mips16-64@mips16-insn-e.l: New stderr output. * testsuite/gas/mips/mips16e-32@mips16-insn-e.l: New stderr output. * testsuite/gas/mips/mips16-32@mips16-insn-t.l: New stderr output. * testsuite/gas/mips/mips16-64@mips16-insn-t.l: New stderr output. * testsuite/gas/mips/mips16e-32@mips16-insn-t.l: New stderr output. * testsuite/gas/mips/mips16-insn-e.s: New test source. * testsuite/gas/mips/mips16-insn-t.s: New test source. * testsuite/gas/mips/mips.exp: Run the new tests. opcodes/ * mips-dis.c (print_insn_mips16): Disallow EXTEND prefix matching for INSN2_SHORT_ONLY opcode table entries. * mips16-opc.c (SH): New macro. (mips16_opcodes): Set SH in `pinfo2' for non-extensible instruction entries: "nop", "addu", "and", "break", "cmp", "daddu", "ddiv", "ddivu", "div", "divu", "dmult", "dmultu", "drem", "dremu", "dsllv", "dsll", "dsrav", "dsra", "dsrlv", "dsrl", "dsubu", "exit", "entry", "jalr", "jal", "jr", "j", "jalrc", "jrc", "mfhi", "mflo", "move", "mult", "multu", "neg", "not", "or", "rem", "remu", "sllv", "sll", "slt", "sltu", "srav", "sra", "srlv", "srl", "subu", "xor", "sdbbp", "seb", "seh", "sew", "zeb", "zeh", "zew" and "extend". binutils/ * testsuite/binutils-all/mips/mips16-extend-insn.d: New test. * testsuite/binutils-all/mips/mips16-extend-insn.s: New test source. * testsuite/binutils-all/mips/mips.exp: Run the new tests.
Diffstat (limited to 'include')
-rw-r--r--include/ChangeLog4
-rw-r--r--include/opcode/mips.h4
2 files changed, 8 insertions, 0 deletions
diff --git a/include/ChangeLog b/include/ChangeLog
index 2f76430..f771bd1 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,7 @@
+2016-12-23 Maciej W. Rozycki <macro@imgtec.com>
+
+ * opcode/mips.h (INSN2_SHORT_ONLY): New macro.
+
2016-12-21 Alan Modra <amodra@gmail.com>
* coff/pe.h: Fix comment chars with high bit set.
diff --git a/include/opcode/mips.h b/include/opcode/mips.h
index 329a698..cf661c8 100644
--- a/include/opcode/mips.h
+++ b/include/opcode/mips.h
@@ -1114,6 +1114,10 @@ mips_opcode_32bit_p (const struct mips_opcode *mo)
#define INSN2_VU0_CHANNEL_SUFFIX 0x00004000
/* Instruction has a forbidden slot. */
#define INSN2_FORBIDDEN_SLOT 0x00008000
+/* Opcode table entry is for a short MIPS16 form only. An extended
+ encoding may still exist, but with a separate opcode table entry
+ required. */
+#define INSN2_SHORT_ONLY 0x00010000
/* Masks used to mark instructions to indicate which MIPS ISA level
they were introduced in. INSN_ISA_MASK masks an enumeration that