i386: Always use TARGET_DEEP_BRANCH_PREDICTION.

While it could be possible to output_set_got such that we can
individually annotate the instructions, it's simpler to simply
admit that all processors currently being manufactured do want
deep branch prediction.  At which point all of the complication
simply goes away.

        * config/i386/i386.h (X86_TUNE_DEEP_BRANCH_PREDICTION): Remove.
        (TARGET_DEEP_BRANCH_PREDICTION): Remove.
        * config/i386/i386.c: Don't include dwarf2out.h.
        (initial_ix86_tune_features): Remove X86_TUNE_DEEP_BRANCH_PREDICTION.
        (output_set_got): Don't test TARGET_DEEP_BRANCH_PREDICTION, delete
        all code dead thereafter.  Don't do dwarf2out_flush_queued_reg_saves.
        (ix86_expand_prologue): Set REG_CFA_FLUSH_QUEUE on set_got insn.
        (machopic_output_stub): Don't test TARGET_DEEP_BRANCH_PREDICTION.

From-SVN: r175730

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 28109773726c69e6f1f4bb7be8083f346ea4984e..3a1b56ae3408a92a0f819387868ffb4749a9bb6a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2011-06-30  Richard Henderson  <rth@redhat.com>
+
+       * config/i386/i386.h (X86_TUNE_DEEP_BRANCH_PREDICTION): Remove.
+       (TARGET_DEEP_BRANCH_PREDICTION): Remove.
+       * config/i386/i386.c: Don't include dwarf2out.h.
+       (initial_ix86_tune_features): Remove X86_TUNE_DEEP_BRANCH_PREDICTION.
+       (output_set_got): Don't test TARGET_DEEP_BRANCH_PREDICTION, delete
+       all code dead thereafter.  Don't do dwarf2out_flush_queued_reg_saves.
+       (ix86_expand_prologue): Set REG_CFA_FLUSH_QUEUE on set_got insn.
+       (machopic_output_stub): Don't test TARGET_DEEP_BRANCH_PREDICTION.
+
 2011-06-30  Richard Henderson  <rth@redhat.com>
 
        * reg-notes.def (REG_CFA_FLUSH_QUEUE): New.

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index b3434dd96d9a36f9960c903c9525ee14d6c9acc4..04cb07d5740f795763f3588d32670bd1900e65b4 100644 (file)
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -55,7 +55,6 @@ along with GCC; see the file COPYING3.  If not see
 #include "params.h"
 #include "cselib.h"
 #include "debug.h"
-#include "dwarf2out.h"
 #include "sched-int.h"
 #include "sbitmap.h"
 #include "fibheap.h"
@@ -1847,10 +1846,6 @@ static unsigned int initial_ix86_tune_features[X86_TUNE_LAST] = {
   m_486 | m_PENT | m_ATOM | m_PPRO | m_AMD_MULTIPLE | m_K6
   | m_CORE2I7 | m_GENERIC,
 
-  /* X86_TUNE_DEEP_BRANCH_PREDICTION */
-  m_ATOM | m_PPRO | m_K6_GEODE | m_AMD_MULTIPLE | m_PENT4
-  | m_CORE2I7 | m_GENERIC,
-
   /* X86_TUNE_BRANCH_PREDICTION_HINTS: Branch hints were put in P4 based
      on simulation result. But after P4 was made, no performance benefit
      was observed with branch hints.  It also increases the code size.
@@ -8331,31 +8326,11 @@ output_set_got (rtx dest, rtx label ATTRIBUTE_UNUSED)
 
   xops[1] = gen_rtx_SYMBOL_REF (Pmode, GOT_SYMBOL_NAME);
 
-  if (! TARGET_DEEP_BRANCH_PREDICTION || !flag_pic)
+  if (!flag_pic)
     {
       xops[2] = gen_rtx_LABEL_REF (Pmode, label ? label : gen_label_rtx ());
 
-      if (!flag_pic)
-       output_asm_insn ("mov%z0\t{%2, %0|%0, %2}", xops);
-      else
-       {
-         output_asm_insn ("call\t%a2", xops);
-#ifdef DWARF2_UNWIND_INFO
-         /* The call to next label acts as a push.  */
-         if (dwarf2out_do_frame ())
-           {
-             rtx insn;
-             start_sequence ();
-             insn = emit_insn (gen_rtx_SET (VOIDmode, stack_pointer_rtx,
-                                            gen_rtx_PLUS (Pmode,
-                                                          stack_pointer_rtx,
-                                                          GEN_INT (-4))));
-             RTX_FRAME_RELATED_P (insn) = 1;
-             dwarf2out_frame_debug (insn, true);
-             end_sequence ();
-           }
-#endif
-       }
+      output_asm_insn ("mov%z0\t{%2, %0|%0, %2}", xops);
 
 #if TARGET_MACHO
       /* Output the Mach-O "canonical" label name ("Lxx$pb") here too.  This
@@ -8366,29 +8341,6 @@ output_set_got (rtx dest, rtx label ATTRIBUTE_UNUSED)
 
       targetm.asm_out.internal_label (asm_out_file, "L",
                                      CODE_LABEL_NUMBER (XEXP (xops[2], 0)));
-
-      if (flag_pic)
-       {
-         output_asm_insn ("pop%z0\t%0", xops);
-#ifdef DWARF2_UNWIND_INFO
-         /* The pop is a pop and clobbers dest, but doesn't restore it
-            for unwind info purposes.  */
-         if (dwarf2out_do_frame ())
-           {
-             rtx insn;
-             start_sequence ();
-             insn = emit_insn (gen_rtx_SET (VOIDmode, dest, const0_rtx));
-             dwarf2out_frame_debug (insn, true);
-             insn = emit_insn (gen_rtx_SET (VOIDmode, stack_pointer_rtx,
-                                            gen_rtx_PLUS (Pmode,
-                                                          stack_pointer_rtx,
-                                                          GEN_INT (4))));
-             RTX_FRAME_RELATED_P (insn) = 1;
-             dwarf2out_frame_debug (insn, true);
-             end_sequence ();
-           }
-#endif
-       }
     }
   else
     {
@@ -8396,12 +8348,6 @@ output_set_got (rtx dest, rtx label ATTRIBUTE_UNUSED)
       get_pc_thunk_name (name, REGNO (dest));
       pic_labels_used |= 1 << REGNO (dest);
 
-#ifdef DWARF2_UNWIND_INFO
-      /* Ensure all queued register saves are flushed before the
-        call.  */
-      if (dwarf2out_do_frame ())
-       dwarf2out_flush_queued_reg_saves ();
-#endif
       xops[2] = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (name));
       xops[2] = gen_rtx_MEM (QImode, xops[2]);
       output_asm_insn ("call\t%X2", xops);
@@ -8416,13 +8362,8 @@ output_set_got (rtx dest, rtx label ATTRIBUTE_UNUSED)
 #endif
     }
 
-  if (TARGET_MACHO)
-    return "";
-
-  if (!flag_pic || TARGET_DEEP_BRANCH_PREDICTION)
+  if (!TARGET_MACHO)
     output_asm_insn ("add%z0\t{%1, %0|%0, %1}", xops);
-  else
-    output_asm_insn ("add%z0\t{%1+[.-%a2], %0|%0, %1+(.-%a2)}", xops);
 
   return "";
 }
@@ -10146,7 +10087,11 @@ ix86_expand_prologue (void)
             insn = emit_insn (gen_set_got_rex64 (pic_offset_table_rtx));
        }
       else
-        insn = emit_insn (gen_set_got (pic_offset_table_rtx));
+       {
+          insn = emit_insn (gen_set_got (pic_offset_table_rtx));
+         RTX_FRAME_RELATED_P (insn) = 1;
+         add_reg_note (insn, REG_CFA_FLUSH_QUEUE, NULL_RTX);
+       }
     }
 
   /* In the pic_reg_used case, make sure that the got load isn't deleted
@@ -28987,12 +28932,7 @@ machopic_output_stub (FILE *file, const char *symb, const char *stub)
   if (MACHOPIC_ATT_STUB)
     switch_to_section (darwin_sections[machopic_picsymbol_stub3_section]);
   else if (MACHOPIC_PURE)
-    {
-      if (TARGET_DEEP_BRANCH_PREDICTION)
-       switch_to_section (darwin_sections[machopic_picsymbol_stub2_section]);
-      else
-    switch_to_section (darwin_sections[machopic_picsymbol_stub_section]);
-    }
+    switch_to_section (darwin_sections[machopic_picsymbol_stub2_section]);
   else
     switch_to_section (darwin_sections[machopic_symbol_stub_section]);
 
@@ -29006,19 +28946,11 @@ machopic_output_stub (FILE *file, const char *symb, const char *stub)
   else if (MACHOPIC_PURE)
     {
       /* PIC stub.  */
-      if (TARGET_DEEP_BRANCH_PREDICTION)
-       {
-         /* 25-byte PIC stub using "CALL get_pc_thunk".  */
-         rtx tmp = gen_rtx_REG (SImode, 2 /* ECX */);
-         output_set_got (tmp, NULL_RTX);       /* "CALL ___<cpu>.get_pc_thunk.cx".  */
-         fprintf (file, "LPC$%d:\tmovl\t%s-LPC$%d(%%ecx),%%ecx\n", label, lazy_ptr_name, label);
-       }
-      else
-       {
-         /* 26-byte PIC stub using inline picbase: "CALL L42 ! L42: pop %eax".  */
-         fprintf (file, "\tcall LPC$%d\nLPC$%d:\tpopl %%ecx\n", label, label);
-         fprintf (file, "\tmovl %s-LPC$%d(%%ecx),%%ecx\n", lazy_ptr_name, label);
-       }
+      /* 25-byte PIC stub using "CALL get_pc_thunk".  */
+      rtx tmp = gen_rtx_REG (SImode, 2 /* ECX */);
+      output_set_got (tmp, NULL_RTX);  /* "CALL ___<cpu>.get_pc_thunk.cx".  */
+      fprintf (file, "LPC$%d:\tmovl\t%s-LPC$%d(%%ecx),%%ecx\n",
+              label, lazy_ptr_name, label);
       fprintf (file, "\tjmp\t*%%ecx\n");
     }
   else
@@ -29047,13 +28979,8 @@ machopic_output_stub (FILE *file, const char *symb, const char *stub)
      compatibility with existing dylibs.  */
   if (MACHOPIC_PURE)
     {
-      /* PIC stubs.  */
-      if (TARGET_DEEP_BRANCH_PREDICTION)
-       /* 25-byte PIC stub using "CALL get_pc_thunk".  */
-       switch_to_section (darwin_sections[machopic_lazy_symbol_ptr2_section]);
-      else
-       /* 26-byte PIC stub using inline picbase: "CALL L42 ! L42: pop %ebx".  */
-  switch_to_section (darwin_sections[machopic_lazy_symbol_ptr_section]);
+      /* 25-byte PIC stub using "CALL get_pc_thunk".  */
+      switch_to_section (darwin_sections[machopic_lazy_symbol_ptr2_section]);
     }
   else
     /* 16-byte -mdynamic-no-pic stub.  */

diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index d9317ed739c93d93d3d76ed147057149a8835b1c..a1ac6b656daf14fefe04a7f79dd4d93677cb6d43 100644 (file)
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -249,7 +249,6 @@ enum ix86_tune_indices {
   X86_TUNE_PUSH_MEMORY,
   X86_TUNE_ZERO_EXTEND_WITH_AND,
   X86_TUNE_UNROLL_STRLEN,
-  X86_TUNE_DEEP_BRANCH_PREDICTION,
   X86_TUNE_BRANCH_PREDICTION_HINTS,
   X86_TUNE_DOUBLE_WITH_ADD,
   X86_TUNE_USE_SAHF,
@@ -324,8 +323,6 @@ extern unsigned char ix86_tune_features[X86_TUNE_LAST];
 #define TARGET_ZERO_EXTEND_WITH_AND \
        ix86_tune_features[X86_TUNE_ZERO_EXTEND_WITH_AND]
 #define TARGET_UNROLL_STRLEN   ix86_tune_features[X86_TUNE_UNROLL_STRLEN]
-#define TARGET_DEEP_BRANCH_PREDICTION \
-       ix86_tune_features[X86_TUNE_DEEP_BRANCH_PREDICTION]
 #define TARGET_BRANCH_PREDICTION_HINTS \
        ix86_tune_features[X86_TUNE_BRANCH_PREDICTION_HINTS]
 #define TARGET_DOUBLE_WITH_ADD ix86_tune_features[X86_TUNE_DOUBLE_WITH_ADD]