+ RiscV: initial implementation of gprof support

  * cleanup

git-svn-id: trunk@48945 -

.gitattributes

@@ -11292,6 +11292,7 @@ rtl/linux/riscv32/sysnr.inc svneol=native#text/plain
 rtl/linux/riscv64/bsyscall.inc svneol=native#text/plain
 rtl/linux/riscv64/si_c.inc svneol=native#text/plain
 rtl/linux/riscv64/si_dll.inc svneol=native#text/plain
+rtl/linux/riscv64/si_g.inc svneol=native#text/plain
 rtl/linux/riscv64/si_prc.inc svneol=native#text/plain
 rtl/linux/riscv64/sighnd.inc svneol=native#text/plain
 rtl/linux/riscv64/sighndh.inc svneol=native#text/plain

rtl/linux/Makefile

@@ -382,7 +382,7 @@ SYSINIT_UNITS=si_prc si_dll si_c
 endif
 ifeq ($(ARCH),riscv64)
 override LOADERS=
-SYSINIT_UNITS=si_prc si_dll si_c
+SYSINIT_UNITS=si_prc si_dll si_c si_g
 endif
 ifeq ($(ARCH),mipsel)
 override FPCOPT+=-Ur

rtl/linux/Makefile.fpc

@@ -98,7 +98,7 @@ endif
 
 ifeq ($(ARCH),riscv64)
 override LOADERS=
-SYSINIT_UNITS=si_prc si_dll si_c
+SYSINIT_UNITS=si_prc si_dll si_c si_g
 endif
 
 # mipsel reuses mips files by including so some file names exist

rtl/linux/riscv64/si_c.inc

@@ -15,12 +15,8 @@
                           Process start/halt
  ******************************************************************************}
 
-var
-  dlexitproc : pointer;
-
 var
   BSS_START: record end; external name '__bss_start';
-  STACK_PTR: record end; external name '__stkptr';
 
   { as we do not call these procedures directly, calling conventions do not matter and
     even if we did, we use c calling conventions anyways }

rtl/linux/riscv64/si_g.inc

@@ -0,0 +1,106 @@
+{
+    This file is part of the Free Pascal run time library.
+    Copyright (c) 2019 by Jeppe Johansen.
+
+    See the file COPYING.FPC, included in this distribution,
+    for details about the copyright.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+ **********************************************************************}
+
+{******************************************************************************
+                          Process start/halt
+ ******************************************************************************}
+{$linklib c}
+{$linklib gcc}
+
+var
+  BSS_START: record end; external name '__bss_start';
+  _etext: pointer; external name '_etext';
+
+{ as we do not call these procedures directly, calling conventions do not matter and
+  even if we did, we use c calling conventions anyways }
+procedure __libc_csu_init; external name '__libc_csu_init';
+procedure __libc_csu_fini; external name '__libc_csu_fini';
+
+procedure libc_start_main(main: TProcedure; argc: ptruint; argv: ppchar; init, fini, rtld_fini: TProcedure; stack_end: pointer); cdecl; external name '__libc_start_main';
+procedure libc_exit(code: ptruint); cdecl; external name 'exit';
+
+procedure monstartup(low_pc,high_pc: pointer); cdecl; external;
+procedure _mcleanup; cdecl; external;
+procedure atexit(p: pointer); cdecl; external;
+
+procedure _FPC_rv_enter(at_exit: TProcedure; sp: pptruint);
+  var
+    argc: ptruint;
+    argv: ppchar;
+  begin
+    argc:=sp[0];
+    argv:=@sp[1];
+
+    initialstkptr:=sp;
+    operatingsystem_parameter_argc:=argc;
+    operatingsystem_parameter_argv:=argv;
+    operatingsystem_parameter_envp:=@sp[argc+2];
+
+    monstartup(@_FPC_rv_enter,@_etext);
+    atexit(@_mcleanup);
+
+    libc_start_main(@PascalMain, argc, argv, @__libc_csu_init, @__libc_csu_fini, at_exit, sp);
+  end;
+
+
+procedure _FPC_proc_start; assembler; nostackframe; public name '_start';
+  asm
+    { set up GP }
+    .option push
+    .option norelax
+.L1:
+    auipc gp, %pcrel_hi(BSS_START+0x800)
+    addi  gp, gp, %pcrel_lo(.L1)
+    .option pop
+
+    { Initialise FP to zero }
+    addi fp, x0, 0
+
+    { atexit is in a0 }
+    addi a1, sp, 0
+    jal x1, _FPC_rv_enter
+  end;
+
+
+procedure _FPC_rv_exit(e:longint); assembler; nostackframe;
+  asm
+    addi  a7, x0, 94
+    ecall
+  end;
+
+
+procedure _FPC_proc_haltproc(e:longint); cdecl; public name '_haltproc';
+  begin
+    while true do
+      begin
+        libc_exit(e);
+        _FPC_rv_exit(e);
+      end;
+  end;
+
+
+ procedure initgp; assembler; nostackframe;
+   asm
+   .Linitgp:
+     .option push
+     .option norelax
+   .L1:
+     auipc gp, %pcrel_hi(BSS_START+0x800)
+     addi  gp, gp, %pcrel_lo(.L1)
+     .option pop
+     jalr x0, x1
+
+     .section ".preinit_array","aw"
+     .dc.a .Linitgp
+     .text
+ end;