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-rw-r--r--gas/gen-sframe.c176
1 files changed, 132 insertions, 44 deletions
diff --git a/gas/gen-sframe.c b/gas/gen-sframe.c
index 2d1c196..f5cf9bd 100644
--- a/gas/gen-sframe.c
+++ b/gas/gen-sframe.c
@@ -21,6 +21,7 @@
#include "as.h"
#include "subsegs.h"
#include "sframe.h"
+#include "sframe-internal.h"
#include "gen-sframe.h"
#include "dw2gencfi.h"
@@ -134,10 +135,26 @@ sframe_fre_set_cfa_base_reg (struct sframe_row_entry *fre,
fre->merge_candidate = false;
}
+static offsetT
+sframe_fre_get_cfa_offset (const struct sframe_row_entry * fre)
+{
+ offsetT offset = fre->cfa_offset;
+
+ /* For s390x undo adjustment of CFA offset (to enable 8-bit offsets). */
+ if (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG)
+ offset = SFRAME_V2_S390X_CFA_OFFSET_DECODE (offset);
+
+ return offset;
+}
+
static void
sframe_fre_set_cfa_offset (struct sframe_row_entry *fre,
offsetT cfa_offset)
{
+ /* For s390x adjust CFA offset to enable 8-bit offsets. */
+ if (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG)
+ cfa_offset = SFRAME_V2_S390X_CFA_OFFSET_ENCODE (cfa_offset);
+
fre->cfa_offset = cfa_offset;
fre->merge_candidate = false;
}
@@ -313,7 +330,7 @@ get_num_sframe_fres (void);
/* Get CFA base register ID as represented in SFrame Frame Row Entry. */
static unsigned int
-get_fre_base_reg_id (struct sframe_row_entry *sframe_fre)
+get_fre_base_reg_id (const struct sframe_row_entry *sframe_fre)
{
unsigned int cfi_insn_cfa_base_reg = sframe_fre->cfa_base_reg;
unsigned fre_base_reg = SFRAME_BASE_REG_SP;
@@ -331,7 +348,7 @@ get_fre_base_reg_id (struct sframe_row_entry *sframe_fre)
/* Get number of offsets necessary for the SFrame Frame Row Entry. */
static unsigned int
-get_fre_num_offsets (struct sframe_row_entry *sframe_fre)
+get_fre_num_offsets (const struct sframe_row_entry *sframe_fre)
{
/* Atleast 1 must always be present (to recover CFA). */
unsigned int fre_num_offsets = 1;
@@ -339,7 +356,10 @@ get_fre_num_offsets (struct sframe_row_entry *sframe_fre)
if (sframe_fre->bp_loc == SFRAME_FRE_ELEM_LOC_STACK)
fre_num_offsets++;
if (sframe_ra_tracking_p ()
- && sframe_fre->ra_loc == SFRAME_FRE_ELEM_LOC_STACK)
+ && (sframe_fre->ra_loc == SFRAME_FRE_ELEM_LOC_STACK
+ /* For s390x account padding RA offset, if FP without RA saved. */
+ || (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG
+ && sframe_fre->bp_loc == SFRAME_FRE_ELEM_LOC_STACK)))
fre_num_offsets++;
return fre_num_offsets;
}
@@ -348,7 +368,7 @@ get_fre_num_offsets (struct sframe_row_entry *sframe_fre)
SFrame frame row entry. */
static unsigned int
-sframe_get_fre_offset_size (struct sframe_row_entry *sframe_fre)
+sframe_get_fre_offset_size (const struct sframe_row_entry *sframe_fre)
{
unsigned int max_offset_size = 0;
unsigned int cfa_offset_size = 0;
@@ -361,9 +381,15 @@ sframe_get_fre_offset_size (struct sframe_row_entry *sframe_fre)
cfa_offset_size = get_offset_size_in_bytes (sframe_fre->cfa_offset);
if (sframe_fre->bp_loc == SFRAME_FRE_ELEM_LOC_STACK)
bp_offset_size = get_offset_size_in_bytes (sframe_fre->bp_offset);
- if (sframe_ra_tracking_p ()
- && sframe_fre->ra_loc == SFRAME_FRE_ELEM_LOC_STACK)
- ra_offset_size = get_offset_size_in_bytes (sframe_fre->ra_offset);
+ if (sframe_ra_tracking_p ())
+ {
+ if (sframe_fre->ra_loc == SFRAME_FRE_ELEM_LOC_STACK)
+ ra_offset_size = get_offset_size_in_bytes (sframe_fre->ra_offset);
+ /* For s390x account padding RA offset, if FP without RA saved. */
+ else if (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG
+ && sframe_fre->bp_loc == SFRAME_FRE_ELEM_LOC_STACK)
+ ra_offset_size = get_offset_size_in_bytes (SFRAME_FRE_RA_OFFSET_INVALID);
+ }
/* Get the maximum size needed to represent the offsets. */
max_offset_size = cfa_offset_size;
@@ -523,7 +549,7 @@ sframe_fde_free (struct sframe_func_entry *sframe_fde)
static void
output_sframe_row_entry (symbolS *fde_start_addr,
symbolS *fde_end_addr,
- struct sframe_row_entry *sframe_fre)
+ const struct sframe_row_entry *sframe_fre)
{
unsigned char fre_info;
unsigned int fre_num_offsets;
@@ -542,7 +568,7 @@ output_sframe_row_entry (symbolS *fde_start_addr,
create_fre_start_addr_exp (&exp, sframe_fre->pc_begin, fde_start_addr,
fde_end_addr);
frag_grow (fre_addr_size);
- frag_var (rs_sframe, fre_addr_size, 0, (relax_substateT) 0,
+ frag_var (rs_sframe, fre_addr_size, 0, 0,
make_expr_symbol (&exp), 0, (char *) frag_now);
#else
gas_assert (fde_end_addr);
@@ -569,11 +595,20 @@ output_sframe_row_entry (symbolS *fde_start_addr,
fre_offset_func_map[idx].out_func (sframe_fre->cfa_offset);
fre_write_offsets++;
- if (sframe_ra_tracking_p ()
- && sframe_fre->ra_loc == SFRAME_FRE_ELEM_LOC_STACK)
+ if (sframe_ra_tracking_p ())
{
- fre_offset_func_map[idx].out_func (sframe_fre->ra_offset);
- fre_write_offsets++;
+ if (sframe_fre->ra_loc == SFRAME_FRE_ELEM_LOC_STACK)
+ {
+ fre_offset_func_map[idx].out_func (sframe_fre->ra_offset);
+ fre_write_offsets++;
+ }
+ /* For s390x write padding RA offset, if FP without RA saved. */
+ else if (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG
+ && sframe_fre->bp_loc == SFRAME_FRE_ELEM_LOC_STACK)
+ {
+ fre_offset_func_map[idx].out_func (SFRAME_FRE_RA_OFFSET_INVALID);
+ fre_write_offsets++;
+ }
}
if (sframe_fre->bp_loc == SFRAME_FRE_ELEM_LOC_STACK)
{
@@ -589,7 +624,7 @@ output_sframe_row_entry (symbolS *fde_start_addr,
static void
output_sframe_funcdesc (symbolS *start_of_fre_section,
symbolS *fre_symbol,
- struct sframe_func_entry *sframe_fde)
+ const struct sframe_func_entry *sframe_fde)
{
expressionS exp;
symbolS *dw_fde_start_addrS, *dw_fde_end_addrS;
@@ -598,7 +633,8 @@ output_sframe_funcdesc (symbolS *start_of_fre_section,
dw_fde_start_addrS = get_dw_fde_start_addrS (sframe_fde->dw_fde);
dw_fde_end_addrS = get_dw_fde_end_addrS (sframe_fde->dw_fde);
- /* Start address of the function. */
+ /* Start address of the function. gas always emits this value with encoding
+ SFRAME_F_FDE_FUNC_START_PCREL. See PR ld/32666. */
exp.X_op = O_subtract;
exp.X_add_symbol = dw_fde_start_addrS; /* to location. */
exp.X_op_symbol = symbol_temp_new_now (); /* from location. */
@@ -637,8 +673,8 @@ output_sframe_funcdesc (symbolS *start_of_fre_section,
create_func_info_exp (&cexp, dw_fde_end_addrS, dw_fde_start_addrS,
func_info);
frag_grow (1); /* Size of func info is unsigned char. */
- frag_var (rs_sframe, 1, 0, (relax_substateT) 0,
- make_expr_symbol (&cexp), 0, (char *) frag_now);
+ frag_var (rs_sframe, 1, 0, 0, make_expr_symbol (&cexp), 0,
+ (char *) frag_now);
#else
out_one (func_info);
#endif
@@ -663,8 +699,9 @@ output_sframe_internal (void)
int fixed_ra_offset = SFRAME_CFA_FIXED_RA_INVALID;
/* The function descriptor entries as dumped by the assembler are not
- sorted on PCs. */
- unsigned char sframe_flags = 0;
+ sorted on PCs. Fix for PR ld/32666 requires setting of an additional
+ flag in SFrame Version 2. */
+ unsigned char sframe_flags = SFRAME_F_FDE_FUNC_START_PCREL;
unsigned int num_fdes = get_num_sframe_fdes ();
unsigned int num_fres = get_num_sframe_fres ();
@@ -680,6 +717,10 @@ output_sframe_internal (void)
/* Output the preamble of SFrame section. */
out_two (SFRAME_MAGIC);
out_one (SFRAME_VERSION);
+ /* gas must ensure emitted SFrame sections have at least the required flags
+ set. */
+ gas_assert ((sframe_flags & SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS)
+ == SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS);
out_one (sframe_flags);
/* abi/arch. */
#ifdef sframe_get_abi_arch
@@ -707,7 +748,7 @@ output_sframe_internal (void)
}
out_one (fixed_ra_offset);
- /* None of the AMD64, or AARCH64 ABIs need the auxiliary header.
+ /* None of the AMD64, AARCH64, or s390x ABIs need the auxiliary header.
When the need does arise to use this field, the appropriate backend
must provide this information. */
out_one (0); /* Auxiliary SFrame header length. */
@@ -856,7 +897,7 @@ sframe_xlate_ctx_finalize (struct sframe_xlate_ctx *xlate_ctx,
static void
sframe_xlate_ctx_add_fre (struct sframe_xlate_ctx *xlate_ctx,
- struct sframe_row_entry *fre)
+ struct sframe_row_entry *fre)
{
gas_assert (xlate_ctx && fre);
@@ -883,7 +924,7 @@ sframe_xlate_ctx_add_fre (struct sframe_xlate_ctx *xlate_ctx,
static void
sframe_row_entry_initialize (struct sframe_row_entry *cur_fre,
- struct sframe_row_entry *prev_fre)
+ const struct sframe_row_entry *prev_fre)
{
gas_assert (prev_fre);
cur_fre->cfa_base_reg = prev_fre->cfa_base_reg;
@@ -917,7 +958,7 @@ sframe_register_name (unsigned int reg)
static int
sframe_xlate_do_advance_loc (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
struct sframe_row_entry *last_fre = xlate_ctx->last_fre;
/* Get the scratchpad FRE currently being updated as the cfi_insn's
@@ -963,7 +1004,7 @@ sframe_xlate_do_advance_loc (struct sframe_xlate_ctx *xlate_ctx,
static int
sframe_xlate_do_def_cfa (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
/* Get the scratchpad FRE. This FRE will eventually get linked in. */
@@ -998,9 +1039,9 @@ sframe_xlate_do_def_cfa (struct sframe_xlate_ctx *xlate_ctx,
static int
sframe_xlate_do_def_cfa_register (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
- struct sframe_row_entry *last_fre = xlate_ctx->last_fre;
+ const struct sframe_row_entry *last_fre = xlate_ctx->last_fre;
/* Get the scratchpad FRE. This FRE will eventually get linked in. */
struct sframe_row_entry *cur_fre = xlate_ctx->cur_fre;
@@ -1018,7 +1059,7 @@ sframe_xlate_do_def_cfa_register (struct sframe_xlate_ctx *xlate_ctx,
}
sframe_fre_set_cfa_base_reg (cur_fre, cfi_insn->u.r);
if (last_fre)
- sframe_fre_set_cfa_offset (cur_fre, last_fre->cfa_offset);
+ sframe_fre_set_cfa_offset (cur_fre, sframe_fre_get_cfa_offset (last_fre));
cur_fre->merge_candidate = false;
@@ -1030,7 +1071,7 @@ sframe_xlate_do_def_cfa_register (struct sframe_xlate_ctx *xlate_ctx,
static int
sframe_xlate_do_def_cfa_offset (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
/* The scratchpad FRE currently being updated with each cfi_insn
being interpreted. This FRE eventually gets linked in into the
@@ -1064,7 +1105,7 @@ sframe_xlate_do_def_cfa_offset (struct sframe_xlate_ctx *xlate_ctx,
static int
sframe_xlate_do_offset (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
/* The scratchpad FRE currently being updated with each cfi_insn
being interpreted. This FRE eventually gets linked in into the
@@ -1110,7 +1151,11 @@ sframe_xlate_do_val_offset (const struct sframe_xlate_ctx *xlate_ctx ATTRIBUTE_U
if (cfi_insn->u.ri.reg == SFRAME_CFA_FP_REG
|| (sframe_ra_tracking_p () && cfi_insn->u.ri.reg == SFRAME_CFA_RA_REG)
/* Ignore SP reg, if offset matches assumed default rule. */
- || (cfi_insn->u.ri.reg == SFRAME_CFA_SP_REG && cfi_insn->u.ri.offset != 0))
+ || (cfi_insn->u.ri.reg == SFRAME_CFA_SP_REG
+ && ((sframe_get_abi_arch () != SFRAME_ABI_S390X_ENDIAN_BIG
+ && cfi_insn->u.ri.offset != 0)
+ || (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG
+ && cfi_insn->u.ri.offset != SFRAME_S390X_SP_VAL_OFFSET))))
{
as_warn (_("no SFrame FDE emitted; %s with %s reg %u"),
cfi_esc_p ? ".cfi_escape DW_CFA_val_offset" : ".cfi_val_offset",
@@ -1122,13 +1167,47 @@ sframe_xlate_do_val_offset (const struct sframe_xlate_ctx *xlate_ctx ATTRIBUTE_U
return SFRAME_XLATE_OK;
}
+/* S390-specific translate DW_CFA_register into SFrame context.
+ Return SFRAME_XLATE_OK if success. */
+
+static int
+s390_sframe_xlate_do_register (struct sframe_xlate_ctx *xlate_ctx,
+ const struct cfi_insn_data *cfi_insn)
+{
+ /* The scratchpad FRE currently being updated with each cfi_insn
+ being interpreted. This FRE eventually gets linked in into the
+ list of FREs for the specific function. */
+ struct sframe_row_entry *cur_fre = xlate_ctx->cur_fre;
+
+ gas_assert (cur_fre);
+
+ /* Change the rule for the register indicated by the register number to
+ be the specified register. Encode the register number as offset by
+ shifting it to the left by one and setting the least-significant bit
+ (LSB). The LSB can be used to differentiate offsets from register
+ numbers, as offsets from CFA are always a multiple of -8 on s390x. */
+ if (cfi_insn->u.rr.reg1 == SFRAME_CFA_FP_REG)
+ sframe_fre_set_bp_track (cur_fre,
+ SFRAME_V2_S390X_OFFSET_ENCODE_REGNUM (cfi_insn->u.rr.reg2));
+ else if (sframe_ra_tracking_p ()
+ && cfi_insn->u.rr.reg1 == SFRAME_CFA_RA_REG)
+ sframe_fre_set_ra_track (cur_fre,
+ SFRAME_V2_S390X_OFFSET_ENCODE_REGNUM (cfi_insn->u.rr.reg2));
+
+ return SFRAME_XLATE_OK;
+}
+
/* Translate DW_CFA_register into SFrame context.
Return SFRAME_XLATE_OK if success. */
static int
-sframe_xlate_do_register (struct sframe_xlate_ctx *xlate_ctx ATTRIBUTE_UNUSED,
- struct cfi_insn_data *cfi_insn)
+sframe_xlate_do_register (struct sframe_xlate_ctx *xlate_ctx,
+ const struct cfi_insn_data *cfi_insn)
{
+ /* Conditionally invoke S390-specific implementation. */
+ if (sframe_get_abi_arch () == SFRAME_ABI_S390X_ENDIAN_BIG)
+ return s390_sframe_xlate_do_register (xlate_ctx, cfi_insn);
+
/* Previous value of register1 is register2. However, if the specified
register1 is not interesting (FP or RA reg), the current DW_CFA_register
instruction can be safely skipped without sacrificing the asynchronicity of
@@ -1153,7 +1232,7 @@ sframe_xlate_do_register (struct sframe_xlate_ctx *xlate_ctx ATTRIBUTE_UNUSED,
static int
sframe_xlate_do_remember_state (struct sframe_xlate_ctx *xlate_ctx)
{
- struct sframe_row_entry *last_fre = xlate_ctx->last_fre;
+ const struct sframe_row_entry *last_fre = xlate_ctx->last_fre;
/* If there is no FRE state to remember, nothing to do here. Return
early with non-zero error code, this will cause no SFrame stack trace
@@ -1199,7 +1278,7 @@ sframe_xlate_do_restore_state (struct sframe_xlate_ctx *xlate_ctx)
static int
sframe_xlate_do_restore (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
struct sframe_row_entry *cie_fre = xlate_ctx->first_fre;
/* The scratchpad FRE currently being updated with each cfi_insn
@@ -1207,11 +1286,18 @@ sframe_xlate_do_restore (struct sframe_xlate_ctx *xlate_ctx,
list of FREs for the specific function. */
struct sframe_row_entry *cur_fre = xlate_ctx->cur_fre;
+ /* PR gas/33170. It is valid to have a:
+ .cfi_restore N
+ even at the entry of a function; in which case cie_fre is not yet setup.
+ Point cie_fre to cur_fre, and let the machinery proceed to update
+ merge_candidate as usual. */
+ if (cie_fre == NULL)
+ cie_fre = cur_fre;
+
/* Change the rule for the indicated register to the rule assigned to
- it by the initial_instructions in the CIE. */
- gas_assert (cie_fre);
- /* SFrame FREs track only CFA and FP / RA for backtracing purposes;
- skip the other .cfi_restore directives. */
+ it by the initial_instructions in the CIE. SFrame FREs track only CFA
+ and FP / RA for backtracing purposes; skip the other .cfi_restore
+ directives. */
if (cfi_insn->u.r == SFRAME_CFA_FP_REG)
{
gas_assert (cur_fre);
@@ -1235,7 +1321,7 @@ sframe_xlate_do_restore (struct sframe_xlate_ctx *xlate_ctx,
static int
sframe_xlate_do_aarch64_negate_ra_state (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn ATTRIBUTE_UNUSED)
+ const struct cfi_insn_data *cfi_insn ATTRIBUTE_UNUSED)
{
struct sframe_row_entry *cur_fre = xlate_ctx->cur_fre;
@@ -1252,7 +1338,7 @@ sframe_xlate_do_aarch64_negate_ra_state (struct sframe_xlate_ctx *xlate_ctx,
static int
sframe_xlate_do_aarch64_negate_ra_state_with_pc (struct sframe_xlate_ctx *xlate_ctx ATTRIBUTE_UNUSED,
- struct cfi_insn_data *cfi_insn ATTRIBUTE_UNUSED)
+ const struct cfi_insn_data *cfi_insn ATTRIBUTE_UNUSED)
{
as_warn (_("no SFrame FDE emitted; .cfi_negate_ra_state_with_pc"));
/* The used signing method should be encoded inside the FDE in SFrame v3.
@@ -1272,7 +1358,7 @@ sframe_xlate_do_aarch64_negate_ra_state_with_pc (struct sframe_xlate_ctx *xlate_
static int
sframe_xlate_do_gnu_window_save (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
unsigned char abi_arch = sframe_get_abi_arch ();
@@ -1639,7 +1725,7 @@ sframe_get_cfi_name (int cfi_opc)
static int
sframe_do_cfi_insn (struct sframe_xlate_ctx *xlate_ctx,
- struct cfi_insn_data *cfi_insn)
+ const struct cfi_insn_data *cfi_insn)
{
int err = 0;
@@ -1719,7 +1805,7 @@ static int
sframe_do_fde (struct sframe_xlate_ctx *xlate_ctx,
const struct fde_entry *dw_fde)
{
- struct cfi_insn_data *cfi_insn;
+ const struct cfi_insn_data *cfi_insn;
int err = SFRAME_XLATE_OK;
xlate_ctx->dw_fde = dw_fde;
@@ -1759,7 +1845,9 @@ sframe_do_fde (struct sframe_xlate_ctx *xlate_ctx,
= get_dw_fde_end_addrS (xlate_ctx->dw_fde);
}
- if (sframe_ra_tracking_p ())
+ /* ABI/arch except s390x cannot represent FP without RA saved. */
+ if (sframe_ra_tracking_p ()
+ && sframe_get_abi_arch () != SFRAME_ABI_S390X_ENDIAN_BIG)
{
struct sframe_row_entry *fre;
generated by cgit v1.1 at 2025-09-03 20:39:56 +0000