[binutils-gdb] This patch ensure same output for sleb128 with large number.

[Tristan Gingold <gingold at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=74def31dcd248441a49755721da81ca73d99c4fb

commit 74def31dcd248441a49755721da81ca73d99c4fb
Author: Tristan Gingold <gingold@adacore.com>
Date:   Mon Jan 9 15:50:32 2017 +0100

    This patch ensure same output for sleb128 with large number.
    
    gas/
    	* read.c (emit_leb128_expr): Extended unsigned big number for
    	sleb128.
    	* testsuite/gas/all/gas.exp (test_cond): Add sleb128-8 test.
    	* testsuite/gas/all/sleb128.d: New test.
    	* testsuite/gas/all/sleb128.s: New test source.

Diff:
---
 gas/ChangeLog                     |  8 ++++++++
 gas/read.c                        | 14 +++++++++++---
 gas/testsuite/gas/all/gas.exp     |  1 +
 gas/testsuite/gas/all/sleb128-8.d |  7 +++++++
 gas/testsuite/gas/all/sleb128-8.s |  2 ++
 5 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 0fab5fb..4d364ab 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,11 @@
+2017-01-10  Tristan Gingold  <gingold@adacore.com>
+
+	* read.c (emit_leb128_expr): Extended unsigned big number for
+	sleb128.
+	* testsuite/gas/all/gas.exp (test_cond): Add sleb128-8 test.
+	* testsuite/gas/all/sleb128.d: New test.
+	* testsuite/gas/all/sleb128.s: New test source.
+
 2017-01-09  Andrew Waterman <andrew@sifive.com>
 
 	* config/tc-riscv.c (append_insn): Don't eagerly apply relocations
diff --git a/gas/read.c b/gas/read.c
index 5c0d320..3669b28 100644
--- a/gas/read.c
+++ b/gas/read.c
@@ -5344,13 +5344,21 @@ emit_leb128_expr (expressionS *exp, int sign)
   else if (op == O_big)
     {
       /* O_big is a different sort of constant.  */
-
+      int nbr_digits = exp->X_add_number;
       unsigned int size;
       char *p;
 
-      size = output_big_leb128 (NULL, generic_bignum, exp->X_add_number, sign);
+      /* If the leading littenum is 0xffff, prepend a 0 to avoid confusion with
+	 a signed number.  Unary operators like - or ~ always extend the
+	 bignum to its largest size.  */
+      if (exp->X_unsigned
+	  && nbr_digits < SIZE_OF_LARGE_NUMBER
+	  && generic_bignum[nbr_digits - 1] == LITTLENUM_MASK)
+	generic_bignum[nbr_digits++] = 0;
+
+      size = output_big_leb128 (NULL, generic_bignum, nbr_digits, sign);
       p = frag_more (size);
-      if (output_big_leb128 (p, generic_bignum, exp->X_add_number, sign) > size)
+      if (output_big_leb128 (p, generic_bignum, nbr_digits, sign) > size)
 	abort ();
     }
   else
diff --git a/gas/testsuite/gas/all/gas.exp b/gas/testsuite/gas/all/gas.exp
index 8f97ed8..6b5aec0 100644
--- a/gas/testsuite/gas/all/gas.exp
+++ b/gas/testsuite/gas/all/gas.exp
@@ -393,6 +393,7 @@ run_dump_test sleb128-5
 if { ![istarget "tic4x*-*-*"] && ![istarget "tic54x*-*-*"] } {
     run_dump_test sleb128-7
 }
+run_dump_test sleb128-8
 
 # .byte is 32 bits on tic4x, and .p2align isn't supported on tic54x
 # .space is different on hppa*-hpux.
diff --git a/gas/testsuite/gas/all/sleb128-8.d b/gas/testsuite/gas/all/sleb128-8.d
new file mode 100644
index 0000000..793337c
--- /dev/null
+++ b/gas/testsuite/gas/all/sleb128-8.d
@@ -0,0 +1,7 @@
+#objdump : -s -j .data -j "\$DATA\$"
+#name : .sleb128 tests (8)
+
+.*: .*
+
+Contents of section (\.data|\$DATA\$):
+ 0000 ffffffff ffff3f .*
diff --git a/gas/testsuite/gas/all/sleb128-8.s b/gas/testsuite/gas/all/sleb128-8.s
new file mode 100644
index 0000000..ab3e785
--- /dev/null
+++ b/gas/testsuite/gas/all/sleb128-8.s
@@ -0,0 +1,2 @@
+	.data
+	.sleb128 281474976710655