Re: [PATCH v5 5/6] hppa: Add emulation of Artist graphics

[Philippe Mathieu-Daudé]

Hi Sven,

On 12/20/19 10:15 PM, Sven Schnelle wrote:

This adds emulation of Artist graphics good enough
to get a Text console on both Linux and HP-UX. The
X11 server from HP-UX also works.

Signed-off-by: Sven Schnelle <sv...@stackframe.org>
---
  hw/display/Kconfig       |    4 +
  hw/display/Makefile.objs |    1 +
  hw/display/artist.c      | 1450 ++++++++++++++++++++++++++++++++++++++
  hw/display/trace-events  |    9 +
  hw/hppa/Kconfig          |    1 +
  hw/hppa/hppa_hardware.h  |    1 +
  hw/hppa/machine.c        |    9 +
  7 files changed, 1475 insertions(+)
  create mode 100644 hw/display/artist.c

diff --git a/hw/display/Kconfig b/hw/display/Kconfig
index c500d1fc6d..15d59e10dc 100644
--- a/hw/display/Kconfig
+++ b/hw/display/Kconfig
@@ -91,6 +91,10 @@ config TCX
  config CG3
      bool

+config ARTIST

+    bool
+    select FRAMEBUFFER
+
  config VGA
      bool

diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs

index f2182e3bef..5f03dfdcc4 100644
--- a/hw/display/Makefile.objs
+++ b/hw/display/Makefile.objs
@@ -40,6 +40,7 @@ common-obj-$(CONFIG_SM501) += sm501.o
  common-obj-$(CONFIG_TCX) += tcx.o
  common-obj-$(CONFIG_CG3) += cg3.o
  common-obj-$(CONFIG_NEXTCUBE) += next-fb.o
+common-obj-$(CONFIG_ARTIST) += artist.o

obj-$(CONFIG_VGA) += vga.o diff --git a/hw/display/artist.c b/hw/display/artist.c

[...]

+static void draw_line_size(ARTISTState *s, bool update_start)
+{
+
+    int startx = artist_get_x(s->vram_start);
+    int starty = artist_get_y(s->vram_start);
+    int endx = artist_get_x(s->line_size);
+    int endy = artist_get_y(s->line_size);
+
+    trace_artist_draw_line(startx, starty, endx, endy);
+    draw_line(s, startx, starty, endx, endy, update_start, -1, -1);
+}
+
+static void draw_line_xy(ARTISTState *s, bool update_start)
+{
+
+    int startx = artist_get_x(s->vram_start);
+    int starty = artist_get_y(s->vram_start);
+    int sizex = artist_get_x(s->blockmove_size);
+    int sizey = artist_get_y(s->blockmove_size);
+    int linexy = s->line_xy >> 16;
+    int endx, endy;
+
+    endx = startx;
+    endy = starty;
+
+    if (sizex > 0) {
+        endx = startx + linexy;
+    }
+
+    if (sizex < 0) {
+        endx = startx;
+        startx -= linexy;
+    }
+
+    if (sizey > 0) {
+        endy = starty + linexy;
+    }
+
+    if (sizey < 0) {
+        endy = starty;
+        starty -= linexy;
+    }
+
+    if (startx < 0) {
+        startx = 0;
+    }
+
+    if (endx < 0) {
+        endx = 0;

If negative, set to zero.

+    }
+
+    if (starty < 0) {
+        starty = 0;
+    }
+
+    if (endy < 0) {
+        endy = 0;

Ditto.

+    }
+
+
+    if (endx < 0) {
+        return;

Here Coverity points:

>>>     CID 1419388:  Control flow issues  (DEADCODE)
>>>     Execution cannot reach this statement: "return;".

+    }
+
+    if (endy < 0) {
+        return;

Here again.

+    }
+
+    trace_artist_draw_line(startx, starty, endx, endy);
+    draw_line(s, startx, starty, endx, endy, false, -1, -1);
+}
+
+static void draw_line_end(ARTISTState *s, bool update_start)
+{
+
+    int startx = artist_get_x(s->vram_start);
+    int starty = artist_get_y(s->vram_start);
+    int endx = artist_get_x(s->line_end);
+    int endy = artist_get_y(s->line_end);
+
+    trace_artist_draw_line(startx, starty, endx, endy);
+    draw_line(s, startx, starty, endx, endy, update_start, -1, -1);
+}