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[committed 4/5] MIPS16/GAS: Improve non-constant operand error diagnostics
- From: "Maciej W. Rozycki" <macro at imgtec dot com>
- To: <binutils at sourceware dot org>
- Date: Mon, 15 May 2017 14:34:12 +0100
- Subject: [committed 4/5] MIPS16/GAS: Improve non-constant operand error diagnostics
- Authentication-results: sourceware.org; auth=none
- References: <alpine.DEB.2.00.1705102025580.2590@tp.orcam.me.uk>
Improve operand error diagnostics for non-constant expressions used for
a 16-bit immediate, making the message more descriptive and indicating
the offending operand, e.g.:
foo.s:1: Error: invalid operands `lui $2,foo-bar'
will show as:
foo.s:1: Error: operand 2 must be constant `lui $2,foo-bar'
This case does not currently trigger however, for two reasons.
First, for regular MIPS and microMIPS assembly in the case of no match
caused by `match_int_operand' here, the function is always called again
from `mips_ip' via `match_insns', `match_insn' and then `match_operand'
for the same opcode table's entry with `lax_match' set to TRUE, in which
case the attempt to match succeeds and no error is issued.
Second, in the case of MIPS16 assembly no call to `match_int_operand' is
made at all for 16-bit immediates, because such immediates are currently
only matched with extensible instructions, and these are handled in
`match_mips16_insn' via `match_expression' directly rather than via
`match_operand'.
This will change for MIPS16 code with MIPS16e2 support introduced, where
non-extensible instructions accepting 16-bit immediates will be added,
so make the case work well right from the start.
gas/
* config/tc-mips.c (match_int_operand): Call
`match_not_constant' before returning failure for a non-constant
16-bit immediate conditionally allowed.
---
binutils-mips-gas-int-not-const-err.diff
Index: binutils/gas/config/tc-mips.c
===================================================================
--- binutils.orig/gas/config/tc-mips.c 2017-05-12 13:49:05.778390286 +0100
+++ binutils/gas/config/tc-mips.c 2017-05-12 17:01:44.141609779 +0100
@@ -5082,7 +5082,10 @@ match_int_operand (struct mips_arg_info
/* Accept non-constant operands if no later alternative matches,
leaving it for the caller to process. */
if (!arg->lax_match)
- return FALSE;
+ {
+ match_not_constant (arg);
+ return FALSE;
+ }
offset_reloc[0] = BFD_RELOC_LO16;
return TRUE;
}