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[PATCH] cpu/opcodes: Sync up fr30.cpu and generated opcodes files

Andrew Burgess andrew.burgess@embecosm.com
Sun Feb 14 00:44:00 GMT 2016 
In commit b6518b3 (Fix compile time warnings generated when compiling
with clang.) the generated fr30-ibld.c file was modified, but the
underlying fr30.cpu file, from which it is generated was not.

This commit updates the fr30.cpu file in such a way that the C code
generated in fr30-ibld.c avoids the undefined behaviour that b6518b3 was
trying to avoid, while also being something that CGEN can handle without
any changes.

cpu/ChangeLog:

	* fr30.cpu (f-m4): Adjust extract handler to avoid shifting a
	negative value (undefined behaviour in C).

opcodes/ChangeLog:

	* fr30-ibld.c: Regenerate from latest cpu/fr30.cpu file.
---
 cpu/ChangeLog       | 5 +++++
 cpu/fr30.cpu        | 7 +++----
 opcodes/ChangeLog   | 4 ++++
 opcodes/fr30-ibld.c | 2 +-
 4 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/cpu/ChangeLog b/cpu/ChangeLog
index 3d39b91..59782b5 100644
--- a/cpu/ChangeLog
+++ b/cpu/ChangeLog
@@ -1,3 +1,8 @@
+2016-02-14  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* fr30.cpu (f-m4): Adjust extract handler to avoid shifting a
+	negative value (undefined behaviour in C).
+
 2016-02-02  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* epiphany.opc (epiphany_print_insn): Set info->bytes_per_line to
diff --git a/cpu/fr30.cpu b/cpu/fr30.cpu
index 6c8e8ce..de15d1e 100644
--- a/cpu/fr30.cpu
+++ b/cpu/fr30.cpu
@@ -160,10 +160,9 @@
 (df  f-i4        "4 bit sign extended"   ()  8  4 INT #f #f)
 (df  f-m4        "4 bit minus extended"  ()  8  4 UINT
      ((value pc) (and WI value (const #xf)))
-     ; ??? On a 64 bit host this doesn't get completely sign extended
-     ; if the value is recorded in a long, as it is during extraction.
-     ; Various fixes exist, pick one.
-     ((value pc) (or  WI value (sll WI (const -1) (const 4))))
+     ; We want every bit except the least significant 4 set, so take
+     ; the bit INVerse of setting the last significant 4 bits.
+     ((value pc) (or  WI value (inv WI (const #xf))))
 )
 (dnf f-u8        "8 bit unsigned"        ()  8  8)
 (dnf f-i8        "8 bit unsigned"        ()  4  8)
diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index 24c1680..fc52c94 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,7 @@
+2016-02-14  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* fr30-ibld.c: Regenerate from latest cpu/fr30.cpu file.
+
 2016-02-10  Claudiu Zissulescu  <claziss@synopsys.com>
 	    Janek van Oirschot  <jvanoirs@synopsys.com>
 
diff --git a/opcodes/fr30-ibld.c b/opcodes/fr30-ibld.c
index 1293e73..089254b 100644
--- a/opcodes/fr30-ibld.c
+++ b/opcodes/fr30-ibld.c
@@ -881,7 +881,7 @@ fr30_cgen_extract_operand (CGEN_CPU_DESC cd,
       {
         long value;
         length = extract_normal (cd, ex_info, insn_value, 0, 0, 8, 4, 16, total_length, pc, & value);
-        value = ((value) | (((-1UL) << (4))));
+        value = ((value) | ((~ (15))));
         fields->f_m4 = value;
       }
       break;
-- 
2.5.1
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