NDD uses evex prefix, so when segment prefix is also applied, the instruction
could excceed its 15byte limit, especially adding immediates. This could happen
when "e" constraint accepts any UNSPEC_TPOFF/UNSPEC_NTPOFF constant and it will
add the offset to segment register, which will be encoded using segment prefix.
Disable those *POFF constant usage in NDD add alternatives with new constraint.
gcc/ChangeLog:
* config/i386/constraints.md (je): New constraint.
* config/i386/i386-protos.h (x86_no_poff_operand_p): New function to
check any *POFF constant.
* config/i386/i386.cc (x86_no_poff_operand_p): New prototype.
* config/i386/i386.md (*add<mode>_1): Split out je alternative for add.
---
gcc/config/i386/constraints.md | 5 +++++
gcc/config/i386/i386-protos.h | 1 +
gcc/config/i386/i386.cc | 25 +++++++++++++++++++++++++
gcc/config/i386/i386.md | 10 +++++-----
4 files changed, 36 insertions(+), 5 deletions(-)
diff --git a/gcc/config/i386/constraints.md b/gcc/config/i386/constraints.md
index cbee31fa40a..c6b51324294 100644
--- a/gcc/config/i386/constraints.md
+++ b/gcc/config/i386/constraints.md
@@ -433,3 +433,8 @@ (define_address_constraint "jb"
(define_register_constraint "jc"
"TARGET_APX_EGPR && !TARGET_AVX ? GENERAL_GPR16 : GENERAL_REGS")
+
+(define_constraint "je"
+ "@internal constant that do not allow any unspec global offsets"
+ (and (match_operand 0 "x86_64_immediate_operand")
+ (match_test "x86_no_poff_operand_p (op)")))
diff --git a/gcc/config/i386/i386-protos.h b/gcc/config/i386/i386-protos.h
index 3e08eae4e79..5d902e2925b 100644
--- a/gcc/config/i386/i386-protos.h
+++ b/gcc/config/i386/i386-protos.h
@@ -66,6 +66,7 @@ extern bool x86_extended_QIreg_mentioned_p (rtx_insn *);
extern bool x86_extended_reg_mentioned_p (rtx);
extern bool x86_extended_rex2reg_mentioned_p (rtx);
extern bool x86_evex_reg_mentioned_p (rtx [], int);
+extern bool x86_no_poff_operand_p (rtx);
extern bool x86_maybe_negate_const_int (rtx *, machine_mode);
extern machine_mode ix86_cc_mode (enum rtx_code, rtx, rtx);
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 3779d5b1206..47159b06f7d 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -23292,6 +23292,31 @@ x86_evex_reg_mentioned_p (rtx operands[], int nops)
return false;
}
+/* Return true when rtx operand does not contain any UNSPEC_*POFF related
+ constant to avoid APX_NDD instructions excceed encoding length limit. */
+bool
+x86_no_poff_operand_p (rtx operand)
+{
+ if (GET_CODE (operand) == CONST)
+ {
+ rtx op = XEXP (operand, 0);
+ if (GET_CODE (op) == PLUS)
+ op = XEXP (op, 0);
+
+ if (GET_CODE (op) == UNSPEC)
+ {
+ int unspec = XINT (op, 1);
+ return (unspec != UNSPEC_NTPOFF
+ && unspec != UNSPEC_TPOFF
+ && unspec != UNSPEC_DTPOFF
+ && unspec != UNSPEC_GOTTPOFF
+ && unspec != UNSPEC_GOTNTPOFF
+ && unspec != UNSPEC_INDNTPOFF);
+ }
+ }
+ return true;
+}
+
/* If profitable, negate (without causing overflow) integer constant
of mode MODE at location LOC. Return true in this case. */
bool
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 7ddb2cb2a71..ecd06625a7d 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -6359,15 +6359,15 @@ (define_insn_and_split
"*add<dwi>3_doubleword_concat_zext"
"split_double_mode (<DWI>mode, &operands[0], 1, &operands[0], &operands[5]);")
(define_insn "*add<mode>_1"
- [(set (match_operand:SWI48 0 "nonimmediate_operand" "=rm,r,r,r,r,r")
+ [(set (match_operand:SWI48 0 "nonimmediate_operand" "=rm,r,r,r,r,r,r,r")
(plus:SWI48
- (match_operand:SWI48 1 "nonimmediate_operand" "%0,0,r,r,rm,r")
- (match_operand:SWI48 2 "x86_64_general_operand" "re,BM,0,le,re,BM")))
+ (match_operand:SWI48 1 "nonimmediate_operand" "%0,0,r,r,rm,r,m,r")
+ (match_operand:SWI48 2 "x86_64_general_operand"
"re,BM,0,le,r,e,je,BM")))
(clobber (reg:CC FLAGS_REG))]
"ix86_binary_operator_ok (PLUS, <MODE>mode, operands,
ix86_can_use_ndd_p (PLUS))"
{
- bool use_ndd = (which_alternative == 4 || which_alternative == 5);
+ bool use_ndd = (which_alternative >= 4);
switch (get_attr_type (insn))
{
case TYPE_LEA:
@@ -6398,7 +6398,7 @@ (define_insn "*add<mode>_1"
: "add{<imodesuffix>}\t{%2, %0|%0, %2}";
}
}
- [(set_attr "isa" "*,*,*,*,apx_ndd,apx_ndd")
+ [(set_attr "isa" "*,*,*,*,apx_ndd,apx_ndd,apx_ndd,apx_ndd")
(set (attr "type")
(cond [(eq_attr "alternative" "3")
(const_string "lea")
--
2.31.1
