[committed] Fix ICE due to bogus operand predicate in H8 port peepholes

[committed] Fix ICE due to bogus operand predicate in H8 port peepholes

[Jeff Law]

[-- Attachment #1: Type: text/plain, Size: 992 bytes --]


This is a bit more interesting than the last H8 fix.

The H8 has peepholes to optimize masking a value down to a byte.  They
rely on using gen_lowpart to extract the low byte value of the source
operand which works well on the H8 because accessing the low byte of a
reg is particularly cheap.  THey also work on memory operands.

These peepholes don't really work on symbolic operands.  And if one
makes it into the peephole we'll abort in gen_lowpart.

Anyway, the peepholes currently accept "general_operand", which of
course allows those problematical symbolic operands.  Changing the
operand to "nonimmediate_operand" resolves the issue.  Note that
compile-time constants aren't really a concern here as the expression
would have already been simplified.

This fixes a half-dozen failures in the H8 testsuite.  More importantly
it makes it less likely that a test will suddenly fail because of
improvements to constant propagation or forward propagation.

Installing on the trunk.

Jeff

[-- Attachment #2: P --]
[-- Type: text/plain, Size: 1157 bytes --]

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bde3cd4f042..be0aab2c876 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2018-12-03  Jeff Law  <law@redhat.com>
+
+	* config/h8300/h8300.md (low byte masking peepholes): Only accept
+	nonimmediate_operand for the to-be-masked operand.
+
 2018-12-03  Richard Biener  <rguenther@suse.de>
 
 	* tree-ssa-sccvn.c (eliminate_dom_walker::eliminate_stmt): Only
diff --git a/gcc/config/h8300/h8300.md b/gcc/config/h8300/h8300.md
index b3ba7e0f719..9e8f7159846 100644
--- a/gcc/config/h8300/h8300.md
+++ b/gcc/config/h8300/h8300.md
@@ -4647,7 +4647,7 @@
 
 (define_peephole2
   [(set (match_operand:SI 0 "register_operand" "")
-	(match_operand:SI 1 "general_operand" ""))
+	(match_operand:SI 1 "nonimmediate_operand" ""))
    (set (match_dup 0)
 	(and:SI (match_dup 0)
 		(const_int 255)))]
@@ -4666,7 +4666,7 @@
 
 (define_peephole2
   [(set (match_operand 0 "register_operand" "")
-	(match_operand 1 "general_operand" ""))
+	(match_operand 1 "nonimmediate_operand" ""))
    (set (match_operand:SI 2 "register_operand" "")
 	(and:SI (match_dup 2)
 		(match_operand:SI 3 "const_int_qi_operand" "")))]