From b7134fccde8be4343f37c450379b81f890014f6b Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 21 May 2015 05:50:14 -0700
Subject: [PATCH] Allow indirect branch via GOT slot for x32
X32 doesn't support indirect branch via 32-bit memory slot since
indirect branch will load 64-bit address from 64-bit memory slot.
Since x32 GOT slot is 64-bit, we should allow indirect branch via GOT
slot for x32.
gcc/
PR target/66232
* config/i386/constraints.md (Bg): New constraint for GOT memory
operand.
* config/i386/i386.md (*call_got_x32): New pattern.
(*call_value_got_x32): Likewise.
* config/i386/predicates.md (GOT_memory_operand): New predicate.
gcc/testsuite/
PR target/66232
* gcc.target/i386/pr66232-1.c: New test.
* gcc.target/i386/pr66232-2.c: Likewise.
* gcc.target/i386/pr66232-3.c: Likewise.
* gcc.target/i386/pr66232-4.c: Likewise.
* gcc.target/i386/pr66232-5.c: Likewise.
---
gcc/config/i386/constraints.md | 5 +++++
gcc/config/i386/i386.md | 20 ++++++++++++++++++++
gcc/config/i386/predicates.md | 10 ++++++++++
gcc/testsuite/gcc.target/i386/pr66232-1.c | 13 +++++++++++++
gcc/testsuite/gcc.target/i386/pr66232-2.c | 14 ++++++++++++++
gcc/testsuite/gcc.target/i386/pr66232-3.c | 13 +++++++++++++
gcc/testsuite/gcc.target/i386/pr66232-4.c | 13 +++++++++++++
gcc/testsuite/gcc.target/i386/pr66232-5.c | 16 ++++++++++++++++
8 files changed, 104 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/i386/pr66232-1.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66232-2.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66232-3.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66232-4.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr66232-5.c
@@ -146,10 +146,15 @@
"@internal Lower SSE register when avoiding REX prefix and all SSE registers otherwise.")
;; We use the B prefix to denote any number of internal operands:
+;; g GOT memory operand.
;; s Sibcall memory operand, not valid for TARGET_X32
;; w Call memory operand, not valid for TARGET_X32
;; z Constant call address operand.
+(define_constraint "Bg"
+ "@internal GOT memory operand."
+ (match_operand 0 "GOT_memory_operand"))
+
(define_constraint "Bs"
"@internal Sibcall memory operand."
(and (not (match_test "TARGET_X32"))
@@ -11659,6 +11659,15 @@
"* return ix86_output_call_insn (insn, operands[0]);"
[(set_attr "type" "call")])
+;; This covers both call and sibcall since only GOT slot is allowed.
+(define_insn "*call_got_x32"
+ [(call (mem:QI (zero_extend:DI
+ (match_operand:SI 0 "GOT_memory_operand" "Bg")))
+ (match_operand 1))]
+ "TARGET_X32"
+ "* return ix86_output_call_insn (insn, operands[0]);"
+ [(set_attr "type" "call")])
+
(define_insn "*sibcall"
[(call (mem:QI (match_operand:W 0 "sibcall_insn_operand" "UBsBz"))
(match_operand 1))]
@@ -11825,6 +11834,17 @@
"* return ix86_output_call_insn (insn, operands[1]);"
[(set_attr "type" "callv")])
+;; This covers both call and sibcall since only GOT slot is allowed.
+(define_insn "*call_value_got_x32"
+ [(set (match_operand 0)
+ (call (mem:QI
+ (zero_extend:DI
+ (match_operand:SI 1 "GOT_memory_operand" "Bg")))
+ (match_operand 2)))]
+ "TARGET_X32"
+ "* return ix86_output_call_insn (insn, operands[1]);"
+ [(set_attr "type" "callv")])
+
(define_insn "*sibcall_value"
[(set (match_operand 0)
(call (mem:QI (match_operand:W 1 "sibcall_insn_operand" "UBsBz"))
@@ -606,6 +606,16 @@
(and (not (match_test "TARGET_X32"))
(match_operand 0 "sibcall_memory_operand"))))
+;; Return true if OP is a GOT memory operand.
+(define_predicate "GOT_memory_operand"
+ (match_operand 0 "memory_operand")
+{
+ op = XEXP (op, 0);
+ return (GET_CODE (op) == CONST
+ && GET_CODE (XEXP (op, 0)) == UNSPEC
+ && XINT (XEXP (op, 0), 1) == UNSPEC_GOTPCREL);
+})
+
;; Match exactly zero.
(define_predicate "const0_operand"
(match_code "const_int,const_wide_int,const_double,const_vector")
new file mode 100644
@@ -0,0 +1,13 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fpic -fno-plt" } */
+
+extern void bar (void);
+
+void
+foo (void)
+{
+ bar ();
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*.bar@GOTPCREL" { target { ! ia32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*.bar@GOT\\(" { target ia32 } } } */
new file mode 100644
@@ -0,0 +1,14 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fpic -fno-plt" } */
+
+extern void bar (void);
+
+int
+foo (void)
+{
+ bar ();
+ return 0;
+}
+
+/* { dg-final { scan-assembler "call\[ \t\]*.bar@GOTPCREL" { target { ! ia32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*.bar@GOT\\(" { target ia32 } } } */
new file mode 100644
@@ -0,0 +1,13 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fpic -fno-plt" } */
+
+extern int bar (void);
+
+int
+foo (void)
+{
+ return bar ();
+}
+
+/* { dg-final { scan-assembler "jmp\[ \t\]*.bar@GOTPCREL" { target { ! ia32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*.bar@GOT\\(" { target ia32 } } } */
new file mode 100644
@@ -0,0 +1,13 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fpic -fno-plt" } */
+
+extern int bar (void);
+
+int
+foo (void)
+{
+ return bar () + 1;
+}
+
+/* { dg-final { scan-assembler "call\[ \t\]*.bar@GOTPCREL" { target { ! ia32 } } } } */
+/* { dg-final { scan-assembler "call\[ \t\]*.bar@GOT\\(" { target ia32 } } } */
new file mode 100644
@@ -0,0 +1,16 @@
+/* { dg-do compile { target { ! { ia32 } } } } */
+/* { dg-require-effective-target maybe_x32 } */
+/* { dg-options "-O2 -fpic -mx32" } */
+
+extern void (*bar) (void);
+void
+foo (int n)
+{
+ int i;
+ for (i = 0; i < n; i++)
+ {
+ if (!bar)
+ continue;
+ (*bar) ();
+ }
+}
--
1.9.3