Rediscovered a bug in the VAX 4.1 UNIX assembler. It handles $0f0.0 wrong!

The changes is the table insure that $0f0.0 is never generated.

diff --git a/mach/vax4/cg/table b/mach/vax4/cg/table
index 8525405..941cf0c 100644 (file)
--- a/mach/vax4/cg/table
+++ b/mach/vax4/cg/table
@@ -77,6 +77,7 @@ CONST1 =      {INT num;}              4 cost=(4,3)  "$%[num]"
 CONST2 =       {INT num;}              4 cost=(4,3)  "$%[num]"
 CONST4 =       {INT num;}              4 cost=(4,3)  "$%[num]"
 CONST8 =       {STRING ind;}           8 cost=(8,6)  "$%[ind]"
+FCONST4 =      {INT num;}              4 cost=(4,3)  "$0f%[num].0"
 FCONST8 =      {INT num;}              8 cost=(8,6)  "$0f%[num].0"
 LOCAL1 =       {REGISTER reg; INT num,size;}   4 cost=(2,6)  "%[num](%[reg])"
 LOCAL2 =       {REGISTER reg; INT num,size;}   4 cost=(2,6)  "%[num](%[reg])"
@@ -182,7 +183,7 @@ source2 =   regdef2 + displ2 + displdef2 +
                + reginc2 + regdec2
 #endif REGVARS
 source4 =      REG + regdef4 + displ4 + displdef4 + LocaLBase +
-               EXTERNAL4 + reldef4 + CONST + DOUBLE + LOCAL4
+               EXTERNAL4 + reldef4 + CONST + DOUBLE + LOCAL4 + FCONST4
                + extind4 + displind4 + extdefind4 + displdefind4
 #ifdef REGVARS
                + RREG + reginc4 + regdec4
@@ -191,7 +192,7 @@ dups4 =             CONST + regdef1 + displ1 + LOCAL1 +
                REG +   regdef2 + displ2 + LOCAL2 +
                RREG +  regdef4 + displ4 + LOCAL4 + DOUBLE
 source8 =      QREG + regdef8 + displ8 + displdef8 +
-               EXTERNAL8 + reldef8 + CONST8 + LOCAL8
+               EXTERNAL8 + reldef8 + CONST8 + LOCAL8 + FCONST8
                + extind8 + displind8 + extdefind8 + displdefind8
 #ifdef REGVARS
                + reginc8 + regdec8
@@ -244,7 +245,7 @@ reg8 =              QREG
 sreg4 =        REG * SCRATCH
 sreg8 =        QREG * SCRATCH
 bigsource4 =   source1or2or4 + nonexist
-bigsource8 =   source8 + FCONST8
+bigsource8 =   source8
 all =          bigsource4 + bigsource8
 scr =          ALL - (EXTERNALS + LOCALS + ADDR_LOCAL + ADDR_EXTERNAL + CONST
                        + DOUBLE)
@@ -264,7 +265,6 @@ CODE:
 loc $1>=0 && $1<256    | |     | {CONST1,$1}                           | |
 loc $1>=256 && $1<65536        | |     | {CONST2,$1}                           | |
 loc            | |             | {CONST4,$1}                           | |
-loc loc $1==0 && $2==0 | |     | {FCONST8,0}                           | |
 ldc            | |             | {CONST8,$1}                           | |
 #ifdef REGVARS
 lol inreg($1)==2 | |           | regvar($1)                            | |
@@ -1986,9 +1986,14 @@ zrl zrl $1==$2-4 | |                             |       | zrl $2 zrl $1 |
 zre            | |     remove(externals)
                        "clrl\t$1"
                        setcc({EXTERNAL4,$1})   |       | |
-zrf $1==4      | |             | {CONST4,0}            | |
-zrf $1==8      | |             | {FCONST8,0}           | |
-zer $1==4      | |             | {CONST4,0}                            | |
+/* Avoid a bug in the VAX assembler, that handles $0f0.0 wrong.
+   So, do NOT create {FCONST[4|8], 0}!
+*/
+zrf $1==4      | |     allocate(REG)
+                       "clrl\t%[a]"            | %[a]  | |
+zrf $1==8      | |     allocate(QREG)
+                       "clrq\t%[a]"            | %[a]  | |
+zer $1==4      | |             | {CONST4,0}            | |
 zer $1==8      | |     allocate(QREG)
                        "clrq\t%[a]"            | %[a]  | |
 zer $1<=32     | STACK |
@@ -2183,6 +2188,8 @@ loc loc cif stl $1==4 && $2==4 && $4>=0
 loc loc cif ste $1==4 && $2==4 | source4 |
                        remove(externals)
                        "cvtlf\t%[1],$4"        |       | |
+loc loc loc cif $1!=0 && $2==4 && $3==4        | |     | {FCONST4, $1} | |
+/* $1 != 0: kludge to avoid bug in VAX assembler */
 #endif FLOAT4
 loc loc cif $1==4 && $2==4     | source4 |
                        allocate(%[1],REG)
@@ -4520,6 +4527,10 @@ MOVES:
                                setcc(%[2]),            (2,4)+%[2])
 (CONST8 %[ind]=="0",source8,   "clrq\t%[2]"
                                setcc(%[2]),            (2,4)+%[2])
+(FCONST4 %[num]==0,source4,    "clrl\t%[2]"
+                               setcc(%[2]),            (2,4)+%[2])
+(FCONST4,source4,              "movl\t%[1],%[2]"
+                               setcc(%[2]),            (3,4)+%[1]+%[2])
 (FCONST8 %[num]==0,source8,    "clrq\t%[2]"
                                setcc(%[2]),            (2,4)+%[2])
 (FCONST8,source8,              "movd\t%[1],%[2]"
@@ -4592,6 +4603,7 @@ STACKS:
 (source8,,     "movq\t%[1],-(sp)"
                setcc(%[1]),            (3,10)+ %[1])
 (nonexist1,,   "pushal\t%[1]",         (2,7) + %[1])
+(FCONST4,,     "pushl\t%[1]",          (2,7) + %[1])
 (FCONST8 %[num]==0,,
                "clrq\t-(sp)",          (2,10))
 (FCONST8,,     "movd\t%[1],-(sp)",     (3,10) + %[1])