From: Stas Boukarev <stassats@gmail.com>
Date: Tue, 6 Aug 2013 17:11:16 +0000 (+0400)
Subject: Fix undefined function errors on PPC and MIPS.
X-Git-Url: http://repo.macrolet.net/gitweb/?a=commitdiff_plain;h=1540c1c1d517c58fa9a41629beb65cdce7dfafb6;p=sbcl.git

Fix undefined function errors on PPC and MIPS.

undefined_tramp hardcodes the register in which FDEFN resides, but the
format was recently changed (f69e89d..).

Other platforms can be susceptible to this.
A proper fix would avoid hardcoding this by exporting
sc-offset-scn-byte/sc-offset-offset-byte, and register offsets.

Thanks to the GCC Compile Farm project for providing machines for
testing and uncovering this.
---

diff --git a/NEWS b/NEWS
index c90875e..912f5b9 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,8 @@
 changes relative to sbcl-1.1.10
   * enhancement: support building the manual under texinfo version 5.
     (lp#1189146)
+  * bug fix: undefined function errors are now properly reported on PPC and MIPS.
+    (regression since 1.1.9)
 
 changes in sbcl-1.1.10 relative to sbcl-1.1.9:
   * enhancement: ASDF has been updated to 3.0.2.
diff --git a/src/code/sc-offset.lisp b/src/code/sc-offset.lisp
index 1811dd6..0f20089 100644
--- a/src/code/sc-offset.lisp
+++ b/src/code/sc-offset.lisp
@@ -16,6 +16,9 @@
 ;;;; We represent the place where some value is stored with a SC-OFFSET,
 ;;;; which is the SC number and offset encoded as an integer.
 
+;;;; FIXME: this layout is hardcoded in some .S files,
+;;;; undefined_tramp in at least ppc-assem.S and mips-assem.S uses it.
+;;;; Ideally, it shouldn't be hardcoded.
 (defconstant-eqx sc-offset-scn-byte (byte 6 0) #'equalp)
 (defconstant-eqx sc-offset-offset-byte (byte 21 6) #'equalp)
 (def!type sc-offset () '(unsigned-byte 27))
diff --git a/src/runtime/mips-assem.S b/src/runtime/mips-assem.S
index 1982ee8..62b3672 100644
--- a/src/runtime/mips-assem.S
+++ b/src/runtime/mips-assem.S
@@ -392,8 +392,8 @@ lra:	.word	RETURN_PC_HEADER_WIDETAG
 	   See debug-var-io.lisp. */
 	.byte	254
 	/* reg_FDEFN is #14. */
-	.byte	((14 << 5) + sc_DescriptorReg) % 0x100
-	.byte	((14 << 5) + sc_DescriptorReg) / 0x100
+	.byte	((14 << 6) + sc_DescriptorReg) % 0x100
+	.byte	((14 << 6) + sc_DescriptorReg) / 0x100
 	.align	2
 	.set	reorder
 1:	lw	reg_CODE, FDEFN_FUN_OFFSET(reg_FDEFN)
diff --git a/src/runtime/ppc-assem.S b/src/runtime/ppc-assem.S
index 51b6b32..3b6e53f 100644
--- a/src/runtime/ppc-assem.S
+++ b/src/runtime/ppc-assem.S
@@ -654,7 +654,7 @@ CSYMBOL(undefined_tramp):
 	twllei reg_ZERO,trap_Cerror
 	.byte 4
 	.byte UNDEFINED_FUN_ERROR
-	.byte 254, sc_DescriptorReg+0x40, 1 /* 140?  sparc says sc_descriptorReg */
+	.byte 254, sc_DescriptorReg+0x80, 0x2 /* 280 */
 	/* This stuff is for the continuable error.  I don't think there's
 	 * any support for it on the lisp side */
 	.align 2
diff --git a/tests/compiler.pure.lisp b/tests/compiler.pure.lisp
index aa8861d..16436ff 100644
--- a/tests/compiler.pure.lisp
+++ b/tests/compiler.pure.lisp
@@ -150,10 +150,11 @@
 
 ;;; on the PPC, we got the magic numbers in undefined_tramp wrong for
 ;;; a while; fixed by CSR 2002-07-18
-(multiple-value-bind (value error)
-    (ignore-errors (some-undefined-function))
-  (assert (null value))
-  (assert (eq (cell-error-name error) 'some-undefined-function)))
+(with-test (:name :undefined-function-error)
+  (multiple-value-bind (value error)
+      (ignore-errors (some-undefined-function))
+    (assert (null value))
+    (assert (eq (cell-error-name error) 'some-undefined-function))))
 
 ;;; Non-symbols shouldn't be allowed as VARs in lambda lists. (Where VAR
 ;;; is a variable name, as in section 3.4.1 of the ANSI spec.)