MSP430: Fix relocation overflow when using #lo(EXP) macro

gas/ChangeLog:

2020-01-15  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* config/tc-msp430.c (CHECK_RELOC_MSP430): Always generate 430X
	relocations when the target is 430X, except when extracting part of an
	expression.
	(msp430_srcoperand): Adjust comment.
	Initialize the expp member of the msp430_operand_s struct as
	appropriate.
	(msp430_dstoperand): Likewise.
	* testsuite/gas/msp430/msp430.exp: Run new test.
	* testsuite/gas/msp430/reloc-lo-430x.d: New test.
	* testsuite/gas/msp430/reloc-lo-430x.s: New test.

include/ChangeLog:

2020-01-15  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* opcode/msp430.h (enum msp430_expp_e): New.
	(struct msp430_operand_s): Add expp member to struct.

ld/ChangeLog:

2020-01-15  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* testsuite/ld-msp430-elf/msp430-elf.exp: Run new test.
	* testsuite/ld-msp430-elf/reloc-lo-430x.s: New test.

gas/ChangeLog

@@ -1,3 +1,16 @@
+2020-01-15  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* config/tc-msp430.c (CHECK_RELOC_MSP430): Always generate 430X
+	relocations when the target is 430X, except when extracting part of an
+	expression.
+	(msp430_srcoperand): Adjust comment.
+	Initialize the expp member of the msp430_operand_s struct as
+	appropriate.
+	(msp430_dstoperand): Likewise.
+	* testsuite/gas/msp430/msp430.exp: Run new test.
+	* testsuite/gas/msp430/reloc-lo-430x.d: New test.
+	* testsuite/gas/msp430/reloc-lo-430x.s: New test.
+
 2020-01-15  Alan Modra  <amodra@gmail.com>
 
 	* configure.tgt: Add sparc-*-freebsd case.

gas/config/tc-msp430.c

@@ -275,21 +275,21 @@ target_is_430xv2 (void)
   return selected_isa == MSP_ISA_430Xv2;
 }
 
-/* Generate an absolute 16-bit relocation.
-   For the 430X we generate a relocation without linker range checking
-    if the value is being used in an extended (ie 20-bit) instruction,
-    otherwise if have a shifted expression we use a HI reloc.
+/* Generate an absolute 16-bit relocation, for 430 (!extended_op) instructions
+   only.
+   For the 430X we generate a 430 relocation only for the case where part of an
+   expression is being extracted (e.g. #hi(EXP), #lo(EXP). Otherwise generate
+   a 430X relocation.
    For the 430 we generate a relocation without assembler range checking
-    if we are handling an immediate value or a byte-width instruction.  */
+   if we are handling an immediate value or a byte-width instruction.  */
 
 #undef  CHECK_RELOC_MSP430
 #define CHECK_RELOC_MSP430(OP)				\
   (target_is_430x ()					\
-  ? (extended_op					\
-     ? BFD_RELOC_16					\
-     : ((OP).vshift == 1)				\
-     ? BFD_RELOC_MSP430_ABS_HI16			\
-     : BFD_RELOC_MSP430X_ABS16)				\
+   ? ((OP).expp == MSP_EXPP_ALL				\
+       ? BFD_RELOC_MSP430X_ABS16			\
+       : ((OP).vshift == 1				\
+	  ? BFD_RELOC_MSP430_ABS_HI16 : BFD_RELOC_16))	\
    : ((imm_op || byte_op)				\
       ? BFD_RELOC_MSP430_16_BYTE : BFD_RELOC_MSP430_16))
 
@@ -1909,13 +1909,15 @@ msp430_srcoperand (struct msp430_operand_s * op,
       char *h = l;
       int vshift = -1;
       int rval = 0;
+      /* Use all parts of the constant expression by default.  */
+      enum msp430_expp_e expp = MSP_EXPP_ALL;
 
       /* Check if there is:
 	 llo(x) - least significant 16 bits, x &= 0xffff
 	 lhi(x) - x = (x >> 16) & 0xffff,
 	 hlo(x) - x = (x >> 32) & 0xffff,
 	 hhi(x) - x = (x >> 48) & 0xffff
-	 The value _MUST_ be constant expression: #hlo(1231231231).  */
+	 The value _MUST_ be an immediate expression: #hlo(1231231231).  */
 
       *imm_op = TRUE;
 
@@ -1923,31 +1925,37 @@ msp430_srcoperand (struct msp430_operand_s * op,
 	{
 	  vshift = 0;
 	  rval = 3;
+	  expp = MSP_EXPP_LLO;
 	}
       else if (strncasecmp (h, "#lhi(", 5) == 0)
 	{
 	  vshift = 1;
 	  rval = 3;
+	  expp = MSP_EXPP_LHI;
 	}
       else if (strncasecmp (h, "#hlo(", 5) == 0)
 	{
 	  vshift = 2;
 	  rval = 3;
+	  expp = MSP_EXPP_HLO;
 	}
       else if (strncasecmp (h, "#hhi(", 5) == 0)
 	{
 	  vshift = 3;
 	  rval = 3;
+	  expp = MSP_EXPP_HHI;
 	}
       else if (strncasecmp (h, "#lo(", 4) == 0)
 	{
 	  vshift = 0;
 	  rval = 2;
+	  expp = MSP_EXPP_LO;
 	}
       else if (strncasecmp (h, "#hi(", 4) == 0)
 	{
 	  vshift = 1;
 	  rval = 2;
+	  expp = MSP_EXPP_HI;
 	}
 
       op->reg = 0;		/* Reg PC.  */
@@ -1956,6 +1964,7 @@ msp430_srcoperand (struct msp430_operand_s * op,
       __tl = h + 1 + rval;
       op->mode = OP_EXP;
       op->vshift = vshift;
+      op->expp = expp;
 
       end = parse_exp (__tl, &(op->exp));
       if (end != NULL && *end != 0 && *end != ')' )
@@ -2167,6 +2176,7 @@ msp430_srcoperand (struct msp430_operand_s * op,
 	}
       op->mode = OP_EXP;
       op->vshift = 0;
+      op->expp = MSP_EXPP_ALL;
       if (op->exp.X_op == O_constant)
 	{
 	  int x = op->exp.X_add_number;
@@ -2275,6 +2285,7 @@ msp430_srcoperand (struct msp430_operand_s * op,
       *h = 0;
       op->mode = OP_EXP;
       op->vshift = 0;
+      op->expp = MSP_EXPP_ALL;
       end = parse_exp (__tl, &(op->exp));
       if (end != NULL && *end != 0)
 	{
@@ -2348,6 +2359,7 @@ msp430_srcoperand (struct msp430_operand_s * op,
   op->am = (*l == '-' ? 3 : 1);
   op->ol = 1;
   op->vshift = 0;
+  op->expp = MSP_EXPP_ALL;
   __tl = l;
   end = parse_exp (__tl, &(op->exp));
   if (end != NULL && * end != 0)
@@ -2382,6 +2394,7 @@ msp430_dstoperand (struct msp430_operand_s * op,
       op->am = 1;
       op->ol = 1;
       op->vshift = 0;
+      op->expp = MSP_EXPP_ALL;
       (void) parse_exp (__tl, &(op->exp));
 
       if (op->exp.X_op != O_constant || op->exp.X_add_number != 0)

gas/testsuite/gas/msp430/msp430.exp

@@ -52,4 +52,5 @@ if [expr [istarget "msp430-*-*"]]  then {
     run_dump_test "attr-430x-large-lower-good"
     run_dump_test "attr-430x-large-any-bad"
     run_dump_test "attr-430x-large-any-good"
+    run_dump_test "reloc-lo-430x"
 }

gas/testsuite/gas/msp430/reloc-lo-430x.d

@@ -0,0 +1,5 @@
+#as: -ml
+#readelf: -r
+#...
+.*R_MSP430_ABS16.*P \+ 0
+#...

gas/testsuite/gas/msp430/reloc-lo-430x.s

@@ -0,0 +1,22 @@
+.text
+	.balign 2
+	.global	foo
+	.type	foo, @function
+foo:
+  MOV.W	#lo (P), R8
+	RETA
+	.size	foo, .-foo
+
+	.balign 2
+	.global	main
+	.type	main, @function
+main:
+	CALLA	#foo
+.L4:
+	BRA	#.L4
+	.size	main, .-main
+	.section	.bss,"aw",@nobits
+	.balign 2
+	.global	P
+P:
+	.zero	4

include/ChangeLog

@@ -1,3 +1,8 @@
+2020-01-15  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* opcode/msp430.h (enum msp430_expp_e): New.
+	(struct msp430_operand_s): Add expp member to struct.
+
 2020-01-13  Claudiu Zissulescu  <claziss@gmail.com>
 
 	* elf/arc-cpu.def: Update ARC cpu list.

include/opcode/msp430.h

@@ -21,6 +21,18 @@
 #ifndef __MSP430_H_
 #define __MSP430_H_
 
+enum msp430_expp_e
+{
+  MSP_EXPP_ALL = 0,	/* Use full the value of the expression - default.  */
+  MSP_EXPP_LO,		/* Extract least significant word from expression.  */
+  MSP_EXPP_HI,		/* Extract 2nd word from expression.  */
+  MSP_EXPP_LLO,		/* Extract least significant word from an
+			   immediate value.  */
+  MSP_EXPP_LHI,		/* Extract 2nd word from an immediate value.  */
+  MSP_EXPP_HLO,		/* Extract 3rd word from an immediate value.  */
+  MSP_EXPP_HHI,		/* Extract 4th word from an immediate value.  */
+};
+
 struct msp430_operand_s
 {
   int ol;	/* Operand length words.  */
@@ -28,6 +40,9 @@ struct msp430_operand_s
   int reg;	/* Register.  */
   int mode;	/* Operand mode.  */
   int vshift;   /* Number of bytes to shift operand down.  */
+  enum msp430_expp_e expp;	/* For when the operand is a constant
+				   expression, the part of the expression to
+				   extract.  */
 #define OP_REG		0
 #define OP_EXP		1
 #ifndef DASM_SECTION

ld/ChangeLog

@@ -1,3 +1,8 @@
+2020-01-15  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* testsuite/ld-msp430-elf/msp430-elf.exp: Run new test.
+	* testsuite/ld-msp430-elf/reloc-lo-430x.s: New test.
+
 2020-01-15  Alan Modra  <amodra@gmail.com>
 
 	* testsuite/ld-powerpc/ambiguousv1b.d: Adjust expected output.

ld/testsuite/ld-msp430-elf/msp430-elf.exp

@@ -174,6 +174,8 @@ run_ld_link_tests $msp430eithershuffletests
 run_ld_link_tests $msp430warntests
 
 run_dump_test valid-map
+run_ld_link_tests {{ "Check no reloc overflow with #lo and data in the upper region"
+        "-m msp430X" "" "" {reloc-lo-430x.s} {} "reloc-lo-430x"}}
 
 # Don't run data region tests if a data region is specified
 if {[string match "*-mdata-region*" [board_info [target_info name] multilib_flags]]} {

ld/testsuite/ld-msp430-elf/reloc-lo-430x.s

@@ -0,0 +1,22 @@
+.text
+	.balign 2
+	.global	foo
+	.type	foo, @function
+foo:
+  MOV.W	#lo (P), R8
+	RETA
+	.size	foo, .-foo
+
+	.balign 2
+	.global	main
+	.type	main, @function
+main:
+	CALLA	#foo
+.L4:
+	BRA	#.L4
+	.size	main, .-main
+	.section	.bss,"aw",@nobits
+	.balign 2
+	.global	P
+P:
+	.zero 4