From d535be87b1014d1a444b7c08f2a44b2d98aa2454 Mon Sep 17 00:00:00 2001
From: David Given <dg@cowlark.com>
Date: Sat, 22 Oct 2016 00:02:15 +0200
Subject: [PATCH] fef4 and fef8 is now cleaner, albeit slower; add some more
 register alias stuff.

---
 mach/powerpc/mcg/platform.c  |  5 +++++
 mach/powerpc/mcg/table       |  6 ++++++
 mach/proto/mcg/hop.c         | 22 ++++++++++++++++---
 mach/proto/mcg/treebuilder.c | 41 ++++++++++--------------------------
 4 files changed, 41 insertions(+), 33 deletions(-)

diff --git a/mach/powerpc/mcg/platform.c b/mach/powerpc/mcg/platform.c
index e3ab26913..e0a7c1a2c 100644
--- a/mach/powerpc/mcg/platform.c
+++ b/mach/powerpc/mcg/platform.c
@@ -202,6 +202,11 @@ struct hop* platform_move(struct basicblock* bb, struct hreg* src, struct hreg*
                     hop_add_insel(hop, "mr %H, %H", dest, src);
                     break;
 
+                case burm_pair_ATTR:
+                    hop_add_insel(hop, "mr %0H, %0H", dest, src);
+                    hop_add_insel(hop, "mr %1H, %1H", dest, src);
+                    break;
+
                 case burm_float_ATTR:
                 case burm_double_ATTR:
                     hop_add_insel(hop, "fmr %H, %H", dest, src);
diff --git a/mach/powerpc/mcg/table b/mach/powerpc/mcg/table
index 236f5c7c1..f1bc27a47 100644
--- a/mach/powerpc/mcg/table
+++ b/mach/powerpc/mcg/table
@@ -162,6 +162,12 @@ PATTERNS
         emit "addi sp, sp, 4"
 		cost 8;
 
+    out:(pair)reg = POP8
+        emit "lwz %out.0, 4(sp)"
+        emit "lwz %out.1, 0(sp)"
+        emit "addi sp, sp, 8"
+        cost 12;
+
 	out:(float)reg = POPF4
 		emit "lfs %out, 0(sp)"
 		emit "addi sp, sp, 4"
diff --git a/mach/proto/mcg/hop.c b/mach/proto/mcg/hop.c
index 9dbb010cc..32bd44d3b 100644
--- a/mach/proto/mcg/hop.c
+++ b/mach/proto/mcg/hop.c
@@ -90,9 +90,25 @@ void hop_add_insel(struct hop* hop, const char* fmt, ...)
     {
         if (*fmt == '%')
         {
+            int index = 0;
             fmt += 2;
+        again:
             switch (fmt[-1])
             {
+                case '0':
+                case '1':
+                case '2':
+                case '3':
+                case '4':
+                case '5':
+                case '6':
+                case '7':
+                case '8':
+                case '9':
+                    index = fmt[-1] - '0';
+                    fmt++;
+                    goto again;
+
                 case 'd':
                     hop_add_string_insel(hop, aprintf("%d", va_arg(ap, int)));
                     break;
@@ -110,11 +126,11 @@ void hop_add_insel(struct hop* hop, const char* fmt, ...)
                     break;
 
                 case 'H':
-                    hop_add_hreg_insel(hop, va_arg(ap, struct hreg*), 0);
+                    hop_add_hreg_insel(hop, va_arg(ap, struct hreg*), index);
                     break;
 
                 case 'V':
-                    hop_add_vreg_insel(hop, va_arg(ap, struct vreg*), 0);
+                    hop_add_vreg_insel(hop, va_arg(ap, struct vreg*), index);
                     break;
             }
         }
@@ -220,7 +236,7 @@ char* hop_render(struct hop* hop)
                 if (hreg)
                     appendf("%s", hreg->brd->names[insel->index]);
                 else
-                    appendf("%%%d", vreg->id);
+                    appendf("%%%d.%d", vreg->id, insel->index);
 				break;
             }
 
diff --git a/mach/proto/mcg/treebuilder.c b/mach/proto/mcg/treebuilder.c
index 7b9ba842c..180f41000 100644
--- a/mach/proto/mcg/treebuilder.c
+++ b/mach/proto/mcg/treebuilder.c
@@ -516,7 +516,7 @@ static void insn_ivalue(int opcode, arith value)
                 new_ir1(
                     IR_LOAD, EM_wordsize,
                     new_ir1(
-                        IR_LOAD, EM_wordsize,
+                        IR_LOAD, EM_pointersize,
                         new_localir(value)
                     )
                 )
@@ -528,7 +528,7 @@ static void insn_ivalue(int opcode, arith value)
                 new_ir2(
                     IR_STORE, EM_wordsize,
                     new_ir1(
-                        IR_LOAD, EM_wordsize,
+                        IR_LOAD, EM_pointersize,
                         new_localir(value)
                     ),
                     pop(EM_wordsize)
@@ -912,41 +912,22 @@ static void insn_ivalue(int opcode, arith value)
         {
             struct ir* e;
             struct ir* f = pop(value);
-            /* fef is implemented by synthesising a call to frexp. */
-            push(
-                new_labelir(".fef_exp")
-            );
-            push(
-                f
-            );
+            /* fef is implemented by calling a helper function which then mutates
+             * the stack. We read the return values off the stack when retracting
+             * the stack pointer. */
+
+            push(f);
+            push(new_wordir(0));
+
             materialise_stack();
             appendir(
                 new_ir1(
                     IR_CALL, 0,
-                    new_labelir((value == 4) ? "frexpf" : "frexp")
+                    new_labelir((value == 4) ? ".fef4" : ".fef8")
                 )
             );
-            appendir(
-                new_ir1(
-                    IR_STACKADJUST, EM_wordsize,
-                    new_wordir(4 + value)
-                )
-            );
-            e = appendir(
-                new_ir0(
-                    IR_GETRET, value
-                )
-            );
-            push(
-                new_ir1(
-                    IR_LOAD, EM_wordsize,
-                    new_labelir(".fef_exp")
-                )
-            );
-            push(
-                e
-            );
                     
+            /* exit, leaving an int and then a float (or double) on the stack. */
             break;
         }