s390: Warn when register name type does not match operand

Print a warning message when the register type of a specified register
name does not match with the operand's register type:

operand {#}: expected {access|control|floating-point|general|vector}
  register name [as {base|index} register]

Introduce a s390-specific assembler option "warn-regtype-mismatch"
with the values "strict", "relaxed", and "no" as well as an option
"no-warn-regtype-mismatch" which control whether the assembler
performs register name type checks and generates above warning messages.

warn-regtype-mismatch=strict:
  Perform strict register name type checks.

warn-regtype-mismatch=relaxed:
  Perform relaxed register name type checks, which allow floating-point
  register (FPR) names %f0 to %f15 to be specified as argument to vector
  register (VR) operands and vector register (VR) names %v0 to %v15 to
  be specified as argument to floating-point register (FPR) operands.
  This is acceptable as the FPRs are embedded into the lower halves of
  the VRs. Make "relaxed" the default, as GCC generates assembler code
  using FPR and VR interchangeably, which would cause assembler warnings
  to be generated with "strict".

warn-regtype-mismatch=no:
no-warn-regtype-mismatch:
  Disable any register name type checks.

Tag .insn pseudo mnemonics as such, to skip register name type checks
on those. They need to be skipped, as there do not exist .insn pseudo
mnemonics for every possible operand register type combination. Keep
track of the currently parsed operand number to provide it as reference
in warning messages.

To verify that the introduction of this change does not unnecessarily
affect the compilation of existing code the GNU Binutils, GNU C Library,
and Linux Kernel have been build with the new assembler, verifying that
the assembler did not generate any of the new warning messages.

gas/
	* config/tc-s390.c: Handle new assembler options
	"[no]warn-regtype-mismatch[=strict|relaxed|no". Annotate
	parsed register expressions with register type. Keep track of
	operand number being parsed. Print warning message in case of
	register type mismatch between instruction operand and parsed
	register expression.
	* doc/as.texi: Document new s390-specific assembler options
	"[no-]warn-regtype-mismatch[=strict|relaxed|no]".
	* NEWS: Mention new s390-specific register name type checks and
	related assembler option "warn-regtype-mismatch=strict|
	relaxed|no".
	* testsuite/gas/s390/s390.exp: Add test cases for new assembler
	option "warn-regtype-mismatch={strict|relaxed}".
	* testsuite/gas/s390/esa-g5.s: Fix register types in tests for
	didbr, diebr, tbdr, and tbedr.
	* testsuite/gas/s390/zarch-z13.s: Fix register types in tests
	for vgef, vgeg, vscef, and vsceg.
	* testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.s:
	Tests for assembler option "warn-regtype-mismatch=strict".
	* testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.l:
	Likewise.
	* gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.s:
	Tests for assembler option "warn-regtype-mismatch=relaxed".
	* gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.l:
	Likewise.
	* gas/testsuite/gas/s390/zarch-omitted-base-index-err.s: Update
	test cases for assembler option "warn-regtype-mismatch"
	defaulting to "relaxed".
	* testsuite/gas/s390/zarch-omitted-base-index-err.l: Likewise.

include/
	* opcode/s390.h (S390_INSTR_FLAG_PSEUDO_MNEMONIC): Add
	instruction flag to tag .insn pseudo-mnemonics.

opcodes/
	* s390-opc.c (s390_opformats): Tag .insn pseudo-mnemonics as
	such.

Reviewed-by: Andreas Krebbel <krebbel@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>

12 files changed, 204 insertions, 22 deletions

diff --git a/gas/NEWS b/gas/NEWS
index 7cf11f2..27be28d 100644
--- a/gas/NEWS
+++ b/gas/NEWS
@@ -1,5 +1,11 @@
 -*- text -*-
 
+* Warn when a register name type does not match the operand type on s390.
+  Add support for s390-specific option "warn-regtype-mismatch=[strict|relaxed|
+  no]" to override the register name type check behavior. The default
+  is "relaxed", which allows floating-point and vector register names to be
+  used interchangeably.
+
 * Add support for 'armv9.5-a' for -march in Arm GAS.
 
 Changes in 2.42:
diff --git a/gas/config/tc-s390.c b/gas/config/tc-s390.c
index eef8428..9659875 100644
--- a/gas/config/tc-s390.c
+++ b/gas/config/tc-s390.c
@@ -60,6 +60,20 @@ static bool reg_names_p = TARGET_REG_NAMES_P;
 /* Set to TRUE if we want to warn about zero base/index registers.  */
 static bool warn_areg_zero = false;
 
+/* Whether to warn about register name type check mismatches.  */
+#ifndef S390_REGTYPE_CHECK
+#define S390_REGTYPE_CHECK S390_REGTYPE_CHECK_RELAXED
+#endif
+
+enum s390_regtype_check {
+  S390_REGTYPE_CHECK_NONE = 0,	/* No register name type checks.  */
+  S390_REGTYPE_CHECK_RELAXED,	/* Relaxed register name type checks.  */
+  S390_REGTYPE_CHECK_STRICT	/* Strict register name type checks.  */
+};
+
+/* Whether to warn about register name type check mismatches.  */
+static enum s390_regtype_check warn_regtype_mismatch = S390_REGTYPE_CHECK;
+
 /* Generic assembler global variables which must be defined by all
    targets.  */
 
@@ -110,6 +124,16 @@ const pseudo_typeS md_pseudo_table[] =
   { NULL,	    NULL,		0 }
 };
 
+/* Register types.  */
+enum s390_register_type
+  {
+    S390_REGTYPE_AR,	/* Access register.  */
+    S390_REGTYPE_CR,	/* Control register.  */
+    S390_REGTYPE_FPR,	/* Floating-point register.  */
+    S390_REGTYPE_GR,	/* General register.  */
+    S390_REGTYPE_VR,	/* Vector register.  */
+  };
+
 /* Given NAME, find the register number associated with that name, return
    the integer value associated with the given name or -1 on failure.  */
 
@@ -180,6 +204,26 @@ register_name (expressionS *expressionP)
     {
       expressionP->X_op = O_register;
       expressionP->X_add_number = reg_number;
+      switch (name[0])
+	{
+	  case 'a':
+	    expressionP->X_md = S390_REGTYPE_AR;
+	    break;
+	  case 'c':
+	    expressionP->X_md = S390_REGTYPE_CR;
+	    break;
+	  case 'f':
+	    expressionP->X_md = S390_REGTYPE_FPR;
+	    break;
+	  case 'r':
+	    expressionP->X_md = S390_REGTYPE_GR;
+	    break;
+	  case 'v':
+	    expressionP->X_md = S390_REGTYPE_VR;
+	    break;
+	  default:
+	    expressionP->X_md = 0;
+	}
 
       /* Make the rest nice.  */
       expressionP->X_add_symbol = NULL;
@@ -415,6 +459,18 @@ md_parse_option (int c, const char *arg)
       else if (arg != NULL && strcmp (arg, "warn-areg-zero") == 0)
 	warn_areg_zero = true;
 
+      else if (arg != NULL && strcmp (arg, "warn-regtype-mismatch=strict") == 0)
+	warn_regtype_mismatch = S390_REGTYPE_CHECK_STRICT;
+
+      else if (arg != NULL && strcmp (arg, "warn-regtype-mismatch=relaxed") == 0)
+	warn_regtype_mismatch = S390_REGTYPE_CHECK_RELAXED;
+
+      else if (arg != NULL && strcmp (arg, "warn-regtype-mismatch=no") == 0)
+	warn_regtype_mismatch = S390_REGTYPE_CHECK_NONE;
+
+      else if (arg != NULL && strcmp (arg, "no-warn-regtype-mismatch") == 0)
+	warn_regtype_mismatch = S390_REGTYPE_CHECK_NONE;
+
       else if (arg != NULL && strcmp (arg, "31") == 0)
 	s390_arch_size = 32;
 
@@ -484,6 +540,13 @@ S390 options:\n\
   -mregnames              allow symbolic names for registers\n\
   -mno-regnames           do not allow symbolic names for registers\n\
   -mwarn-areg-zero        warn about base/index register zero\n\
+  -mwarn-regtype-mismatch=strict\n\
+                          warn about register name type mismatches\n\
+  -mwarn-regtype-mismatch=relaxed\n\
+                          warn about register name type mismatches,\n\
+                          but allow FPR and VR to be used interchangeably\n\
+  -mno-warn-regtype-mismatch\n\
+                          do not warn about register name type mismatches\n\
 "));
   fprintf (stream, _("\
   -V                      print assembler version number\n\
@@ -1279,6 +1342,7 @@ md_gather_operands (char *str,
   elf_suffix_type suffix;
   bfd_reloc_code_real_type reloc;
   int omitted_base_or_index;
+  int operand_number;
   char *f;
   int fc, i;
 
@@ -1287,6 +1351,7 @@ md_gather_operands (char *str,
 
   /* Gather the operands.  */
   omitted_base_or_index = 0;	/* Whether B in D(L,B) or X in D(X,B) were omitted.  */
+  operand_number = 1;		/* Current operand number in e.g. R1,I2,M3,D4(B4).  */
   fc = 0;
   for (opindex_ptr = opcode->operands; *opindex_ptr != 0; opindex_ptr++)
     {
@@ -1378,6 +1443,44 @@ md_gather_operands (char *str,
 		as_bad (_("invalid floating point register pair.  Valid fp "
 			  "register pair operands are 0, 1, 4, 5, 8, 9, "
 			  "12 or 13."));
+	      if (warn_regtype_mismatch && ex.X_op == O_register
+		  && !(opcode->flags & S390_INSTR_FLAG_PSEUDO_MNEMONIC))
+		{
+		  const char *expected_regtype = NULL;
+
+		  if ((operand->flags & S390_OPERAND_AR)
+		      && ex.X_md != S390_REGTYPE_AR)
+		    expected_regtype = _("access register");
+		  else if ((operand->flags & S390_OPERAND_CR)
+			   && ex.X_md != S390_REGTYPE_CR)
+		    expected_regtype = _("control register");
+		  else if ((operand->flags & S390_OPERAND_FPR)
+			   && ex.X_md != S390_REGTYPE_FPR
+			   && (warn_regtype_mismatch == S390_REGTYPE_CHECK_STRICT
+			       || (ex.X_md != S390_REGTYPE_VR)))
+		    expected_regtype = _("floating-point register");
+		  else if ((operand->flags & S390_OPERAND_GPR)
+			   && ex.X_md != S390_REGTYPE_GR)
+		    expected_regtype = _("general register");
+		  else if ((operand->flags & S390_OPERAND_VR)
+			   && ex.X_md != S390_REGTYPE_VR
+			   && (warn_regtype_mismatch == S390_REGTYPE_CHECK_STRICT
+			       || (ex.X_md != S390_REGTYPE_FPR)))
+		    expected_regtype = _("vector register");
+
+		  if (expected_regtype)
+		    {
+		      if (operand->flags & S390_OPERAND_BASE)
+			as_warn (_("operand %d: expected %s name as base register"),
+				 operand_number, expected_regtype);
+		      else if (operand->flags & S390_OPERAND_INDEX)
+			as_warn (_("operand %d: expected %s name as index register"),
+				 operand_number, expected_regtype);
+		      else
+			as_warn (_("operand %d: expected %s name"),
+				 operand_number, expected_regtype);
+		    }
+		}
 	      s390_insert_operand (insn, operand, ex.X_add_number, NULL, 0);
 	    }
 	}
@@ -1516,6 +1619,7 @@ md_gather_operands (char *str,
 		    {
 		      /* Comma.  */
 		      str++;
+		      operand_number++;
 		    }
 		}
 	    }
@@ -1572,6 +1676,7 @@ md_gather_operands (char *str,
 		{
 		  /* Comma.  */
 		  str++;
+		  operand_number++;
 		}
 	    }
 	}
@@ -1610,6 +1715,9 @@ md_gather_operands (char *str,
 		{
 		  /* Comma.  */
 		  str++;
+		  if (!(operand->flags & (S390_OPERAND_INDEX
+					  | S390_OPERAND_LENGTH)))
+		    operand_number++;
 		}
 	    }
 	}
diff --git a/gas/doc/as.texi b/gas/doc/as.texi
index 50c0543..1e122cc 100644
--- a/gas/doc/as.texi
+++ b/gas/doc/as.texi
@@ -584,6 +584,10 @@ gcc(1), ld(1), and the Info entries for @file{binutils} and @file{ld}.
    [@b{-m31}|@b{-m64}] [@b{-mesa}|@b{-mzarch}] [@b{-march}=@var{CPU}]
    [@b{-mregnames}|@b{-mno-regnames}]
    [@b{-mwarn-areg-zero}]
+   [@b{-mwarn-regtype-mismatch=strict}
+    @b{-mwarn-regtype-mismatch=relaxed}
+    @b{-mwarn-regtype-mismatch=no}
+    @b{-mno-warn-regtype-mismatch}]
 @end ifset
 @ifset SCORE
 
@@ -1963,6 +1967,22 @@ Allow or disallow symbolic names for registers.
 @item -mwarn-areg-zero
 Warn whenever the operand for a base or index register has been specified
 but evaluates to zero.
+@item -mwarn-regtype-mismatch=strict
+@itemx -mwarn-regtype-mismatch=relaxed
+@itemx -mwarn-regtype-mismatch=no
+@itemx -mno-warn-regtype-mismatch
+Controls whether the assembler performs register name type checks and generates
+a warning message in case of a mismatch with the operand register type.
+The default (which can be restored by using the @option{relaxed} argument) is
+to perform relaxed register name type checks, which allow floating point
+register (FPR) names %f0 to %f15 to be specified as argument to vector register
+(VR) operands and vector register (VR) names %v0 to %v15 to be specified as
+argument to floating point register (FPR) operands.  This is acceptable as the
+FPR are embedded into the lower half of the VR.
+Using the @option{strict} argument strict register name type checks are
+performed.
+The @option{no} argument, which is equivalent to
+@samp{-mno-warn-regtype-mismatch}, disables any register name type checks.
 @end table
 @end ifset
 @c man end
diff --git a/gas/testsuite/gas/s390/esa-g5.s b/gas/testsuite/gas/s390/esa-g5.s
index 2901a86..812d56e 100644
--- a/gas/testsuite/gas/s390/esa-g5.s
+++ b/gas/testsuite/gas/s390/esa-g5.s
@@ -146,8 +146,8 @@ foo:
 	debr	%f6,%f9
 	der	%f6,%f9
 	diag	%r6,%r9,4095(%r5)
-	didbr	%f6,%r9,%r5,10
-	diebr	%f6,%r9,%r5,10
+	didbr	%f6,%f9,%f5,10
+	diebr	%f6,%f9,%f5,10
 	dp	4095(6,%r5),4095(9,%r10)
 	dr	%r6,%r9
 	dxbr	%f5,%f8
@@ -465,8 +465,8 @@ foo:
 	sxr	%f5,%f8
 	tar	%a6,%r9
 	tb	%r6,%r9
-	tbdr	%r6,5,%r9
-	tbedr	%r6,5,%r9
+	tbdr	%f6,5,%f9
+	tbedr	%f6,5,%f9
 	tcdb	%f6,4095(%r5,%r10)
 	tceb	%f6,4095(%r5,%r10)
 	tcxb	%f5,4095(%r5,%r10)
diff --git a/gas/testsuite/gas/s390/s390.exp b/gas/testsuite/gas/s390/s390.exp
index 613487f..a4e8dbc 100644
--- a/gas/testsuite/gas/s390/s390.exp
+++ b/gas/testsuite/gas/s390/s390.exp
@@ -61,4 +61,6 @@ if [expr [istarget "s390-*-*"] ||  [istarget "s390x-*-*"]]  then {
     run_dump_test "zarch-base-index-0" "{as -m64}"
     run_list_test "zarch-base-index-0-err" ""
     run_list_test "zarch-warn-areg-zero" "-m64 -mwarn-areg-zero"
+    run_list_test "zarch-warn-regtype-mismatch-strict" "-m64 -mwarn-regtype-mismatch=strict"
+    run_list_test "zarch-warn-regtype-mismatch-relaxed" "-m64 -mwarn-regtype-mismatch=relaxed"
 }
diff --git a/gas/testsuite/gas/s390/zarch-omitted-base-index-err.l b/gas/testsuite/gas/s390/zarch-omitted-base-index-err.l
index fe13f95..e4bd7a8 100644
--- a/gas/testsuite/gas/s390/zarch-omitted-base-index-err.l
+++ b/gas/testsuite/gas/s390/zarch-omitted-base-index-err.l
@@ -7,18 +7,19 @@
 .*:9: Error: syntax error; missing '\)' after base register
 .*:12: Error: bad expression
 .*:12: Error: syntax error; missing '\)' after base register
-.*:13: Error: bad expression
-.*:13: Error: syntax error; missing '\)' after base register
-.*:16: Error: missing operand
+.*:13: Warning: operand 2: expected general register name as base register
+.*:14: Error: bad expression
+.*:14: Error: syntax error; missing '\)' after base register
 .*:17: Error: missing operand
-.*:18: Error: invalid length field specified
-.*:19: Error: bad expression
-.*:19: Error: operand out of range \(0 is not between 1 and 256\)
-.*:19: Error: operand out of range \(32 is not between 0 and 15\)
-.*:19: Error: syntax error; missing '\)' after base register
-.*:19: Error: syntax error; expected ','
-.*:19: Error: bad expression
-.*:19: Error: found 'r', expected: '\)'
-.*:19: Error: syntax error; missing '\)' after base register
-.*:19: Error: junk at end of line: `r2\)'
-.*:20: Error: syntax error; missing '\(' after displacement
+.*:18: Error: missing operand
+.*:19: Error: invalid length field specified
+.*:20: Error: bad expression
+.*:20: Error: operand out of range \(0 is not between 1 and 256\)
+.*:20: Error: operand out of range \(32 is not between 0 and 15\)
+.*:20: Error: syntax error; missing '\)' after base register
+.*:20: Error: syntax error; expected ','
+.*:20: Error: bad expression
+.*:20: Error: found 'r', expected: '\)'
+.*:20: Error: syntax error; missing '\)' after base register
+.*:20: Error: junk at end of line: `r2\)'
+.*:21: Error: syntax error; missing '\(' after displacement
diff --git a/gas/testsuite/gas/s390/zarch-omitted-base-index-err.s b/gas/testsuite/gas/s390/zarch-omitted-base-index-err.s
index 65ad739..dd0e9fe 100644
--- a/gas/testsuite/gas/s390/zarch-omitted-base-index-err.s
+++ b/gas/testsuite/gas/s390/zarch-omitted-base-index-err.s
@@ -10,6 +10,7 @@ foo:
 
 #		V1,D2(VX2,B2),M3
 	vgef	%v1,16(%v2,),0
+	vgef	%v1,16(%v2),0
 	vgef	%v1,16(),0
 
 #		D1(L1,B1),D2(B2)
diff --git a/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.l b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.l
new file mode 100644
index 0000000..e91f020
--- /dev/null
+++ b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.l
@@ -0,0 +1,15 @@
+.*: Assembler messages:
+.*:3: Warning: operand 1: expected general register name
+.*:3: Warning: operand 2: expected general register name as index register
+.*:3: Warning: operand 2: expected general register name as base register
+.*:4: Warning: operand 1: expected floating-point register name
+.*:4: Warning: operand 2: expected general register name as index register
+.*:4: Warning: operand 2: expected general register name as base register
+.*:5: Warning: operand 1: expected vector register name
+.*:5: Warning: operand 2: expected general register name as index register
+.*:5: Warning: operand 2: expected general register name as base register
+.*:6: Warning: operand 1: expected vector register name
+.*:6: Warning: operand 2: expected vector register name as index register
+.*:6: Warning: operand 2: expected general register name as base register
+.*:7: Warning: operand 1: expected access register name
+.*:7: Warning: operand 2: expected general register name
diff --git a/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.s b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.s
new file mode 100644
index 0000000..ed6688d
--- /dev/null
+++ b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-relaxed.s
@@ -0,0 +1,7 @@
+.text
+foo:
+	la	%f1,16(%f2,%f3)		# la	%r1,16(%r2,%r3)
+	ld	%r1,16(%f2,%f3)		# ld	%f1,16(%r2,%r3)
+	vl	%r1,16(%f2,%f3),0	# vl	%v1,16(%r2,%r3),0
+	vgef	%r1,16(%r1,%f3),0	# vgef	%v1,16(%v2,%r3),0
+	sar	%r1,%a2			# sar	%a1,%r2
diff --git a/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.l b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.l
new file mode 100644
index 0000000..e91f020
--- /dev/null
+++ b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.l
@@ -0,0 +1,15 @@
+.*: Assembler messages:
+.*:3: Warning: operand 1: expected general register name
+.*:3: Warning: operand 2: expected general register name as index register
+.*:3: Warning: operand 2: expected general register name as base register
+.*:4: Warning: operand 1: expected floating-point register name
+.*:4: Warning: operand 2: expected general register name as index register
+.*:4: Warning: operand 2: expected general register name as base register
+.*:5: Warning: operand 1: expected vector register name
+.*:5: Warning: operand 2: expected general register name as index register
+.*:5: Warning: operand 2: expected general register name as base register
+.*:6: Warning: operand 1: expected vector register name
+.*:6: Warning: operand 2: expected vector register name as index register
+.*:6: Warning: operand 2: expected general register name as base register
+.*:7: Warning: operand 1: expected access register name
+.*:7: Warning: operand 2: expected general register name
diff --git a/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.s b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.s
new file mode 100644
index 0000000..ed6688d
--- /dev/null
+++ b/gas/testsuite/gas/s390/zarch-warn-regtype-mismatch-strict.s
@@ -0,0 +1,7 @@
+.text
+foo:
+	la	%f1,16(%f2,%f3)		# la	%r1,16(%r2,%r3)
+	ld	%r1,16(%f2,%f3)		# ld	%f1,16(%r2,%r3)
+	vl	%r1,16(%f2,%f3),0	# vl	%v1,16(%r2,%r3),0
+	vgef	%r1,16(%r1,%f3),0	# vgef	%v1,16(%v2,%r3),0
+	sar	%r1,%a2			# sar	%a1,%r2
diff --git a/gas/testsuite/gas/s390/zarch-z13.s b/gas/testsuite/gas/s390/zarch-z13.s
index 646dd30..8c2fb70 100644
--- a/gas/testsuite/gas/s390/zarch-z13.s
+++ b/gas/testsuite/gas/s390/zarch-z13.s
@@ -1,8 +1,8 @@
 .text
 foo:
 	lcbb	%r6,4000(%r9,%r11),13
-	vgef	%v15,4000(%r6,%r9),13
-	vgeg	%v15,4000(%r6,%r9),13
+	vgef	%v15,4000(%v6,%r9),13
+	vgeg	%v15,4000(%v6,%r9),13
 	vgbm	%v15,65533
 	vzero	%v15
 	vone	%v15
@@ -83,8 +83,8 @@ foo:
 	vrepih	%v15,-32765
 	vrepif	%v15,-32765
 	vrepig	%v15,-32765
-	vscef	%v15,4000(%r6,%r9),13
-	vsceg	%v15,4000(%r6,%r9),13
+	vscef	%v15,4000(%v6,%r9),13
+	vsceg	%v15,4000(%v6,%r9),13
 	vsel	%v15,%v17,%v20,%v24
 	vseg	%v15,%v17,13
 	vsegb	%v15,%v17