diff mbox series

[for-9.0,1/4] vga: merge conditionals on shift control register

Message ID 20240402113408.18048-2-pbonzini@redhat.com
State New
Headers show
Series vga: fix assertion failure with 4- and 16-color modes | expand

Commit Message

Paolo Bonzini April 2, 2024, 11:34 a.m. UTC 
There are two sets of conditionals using the shift control bits: one to
verify the palette and adjust disp_width, one to compute the "v" and
"bits" variables.  Merge them into one, with the extra benefit that
we now have the "bits" value available early and can use it to
compute region_end.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/display/vga.c | 89 +++++++++++++++++++++++-------------------------
 1 file changed, 42 insertions(+), 47 deletions(-)

Comments

Philippe Mathieu-Daudé April 2, 2024, 11:40 a.m. UTC | #1 
On 2/4/24 13:34, Paolo Bonzini wrote:
> There are two sets of conditionals using the shift control bits: one to
> verify the palette and adjust disp_width, one to compute the "v" and
> "bits" variables.  Merge them into one, with the extra benefit that
> we now have the "bits" value available early and can use it to
> compute region_end.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   hw/display/vga.c | 89 +++++++++++++++++++++++-------------------------
>   1 file changed, 42 insertions(+), 47 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
diff mbox series

Patch

diff --git a/hw/display/vga.c b/hw/display/vga.c
index bc5b83421bf..4795a0012e2 100644
--- a/hw/display/vga.c
+++ b/hw/display/vga.c
@@ -1546,12 +1546,54 @@  static void vga_draw_graphic(VGACommonState *s, int full_update)
     }
 
     if (shift_control == 0) {
+        full_update |= update_palette16(s);
         if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
             disp_width <<= 1;
+            v = VGA_DRAW_LINE4D2;
+        } else {
+            v = VGA_DRAW_LINE4;
         }
+        bits = 4;
+
     } else if (shift_control == 1) {
+        full_update |= update_palette16(s);
         if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
             disp_width <<= 1;
+            v = VGA_DRAW_LINE2D2;
+        } else {
+            v = VGA_DRAW_LINE2;
+        }
+        bits = 4;
+
+    } else {
+        switch (depth) {
+        default:
+        case 0:
+            full_update |= update_palette256(s);
+            v = VGA_DRAW_LINE8D2;
+            bits = 4;
+            break;
+        case 8:
+            full_update |= update_palette256(s);
+            v = VGA_DRAW_LINE8;
+            bits = 8;
+            break;
+        case 15:
+            v = s->big_endian_fb ? VGA_DRAW_LINE15_BE : VGA_DRAW_LINE15_LE;
+            bits = 16;
+            break;
+        case 16:
+            v = s->big_endian_fb ? VGA_DRAW_LINE16_BE : VGA_DRAW_LINE16_LE;
+            bits = 16;
+            break;
+        case 24:
+            v = s->big_endian_fb ? VGA_DRAW_LINE24_BE : VGA_DRAW_LINE24_LE;
+            bits = 24;
+            break;
+        case 32:
+            v = s->big_endian_fb ? VGA_DRAW_LINE32_BE : VGA_DRAW_LINE32_LE;
+            bits = 32;
+            break;
         }
     }
 
@@ -1607,53 +1649,6 @@  static void vga_draw_graphic(VGACommonState *s, int full_update)
         }
     }
 
-    if (shift_control == 0) {
-        full_update |= update_palette16(s);
-        if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
-            v = VGA_DRAW_LINE4D2;
-        } else {
-            v = VGA_DRAW_LINE4;
-        }
-        bits = 4;
-    } else if (shift_control == 1) {
-        full_update |= update_palette16(s);
-        if (sr(s, VGA_SEQ_CLOCK_MODE) & 8) {
-            v = VGA_DRAW_LINE2D2;
-        } else {
-            v = VGA_DRAW_LINE2;
-        }
-        bits = 4;
-    } else {
-        switch(s->get_bpp(s)) {
-        default:
-        case 0:
-            full_update |= update_palette256(s);
-            v = VGA_DRAW_LINE8D2;
-            bits = 4;
-            break;
-        case 8:
-            full_update |= update_palette256(s);
-            v = VGA_DRAW_LINE8;
-            bits = 8;
-            break;
-        case 15:
-            v = s->big_endian_fb ? VGA_DRAW_LINE15_BE : VGA_DRAW_LINE15_LE;
-            bits = 16;
-            break;
-        case 16:
-            v = s->big_endian_fb ? VGA_DRAW_LINE16_BE : VGA_DRAW_LINE16_LE;
-            bits = 16;
-            break;
-        case 24:
-            v = s->big_endian_fb ? VGA_DRAW_LINE24_BE : VGA_DRAW_LINE24_LE;
-            bits = 24;
-            break;
-        case 32:
-            v = s->big_endian_fb ? VGA_DRAW_LINE32_BE : VGA_DRAW_LINE32_LE;
-            bits = 32;
-            break;
-        }
-    }
     vga_draw_line = vga_draw_line_table[v];
 
     if (!is_buffer_shared(surface) && s->cursor_invalidate) {