diff options
author | Edward O'Callaghan <[email protected]> | 2016-12-06 11:28:56 +1100 |
---|---|---|
committer | Edward O'Callaghan <[email protected]> | 2016-12-21 15:00:21 +1100 |
commit | 8801734da701d95608e39d829e0a31a191ee68f2 (patch) | |
tree | 1ca2b2df98ab04d6fd29db8b5f102300f17ea26a /src | |
parent | e827d9175675aaa6cfc0b981e2a80685fb7b3a74 (diff) |
svga: Fix a strict-aliasing violation in shader dumper
As per the C spec, it is illegal to alias pointers to different
types. This results in undefined behaviour after optimization
passes, resulting in very subtle bugs that happen only on a
full moon..
Use a memcpy() as a well defined coercion between the isomorphic
bit-field interpretations of memory.
V.2: Use C99 compat STATIC_ASSERT() over C11 static_assert().
Signed-off-by: Edward O'Callaghan <[email protected]>
Reviewed-by: Charmaine Lee <[email protected]>
Diffstat (limited to 'src')
-rw-r--r-- | src/gallium/drivers/svga/svgadump/svga_shader_dump.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/src/gallium/drivers/svga/svgadump/svga_shader_dump.c b/src/gallium/drivers/svga/svgadump/svga_shader_dump.c index 4ee1bf2c353..46126a5460d 100644 --- a/src/gallium/drivers/svga/svgadump/svga_shader_dump.c +++ b/src/gallium/drivers/svga/svgadump/svga_shader_dump.c @@ -30,6 +30,9 @@ * @author Michal Krol <[email protected]> */ +#include <assert.h> +#include <string.h> + #include "svga_shader.h" #include "svga_shader_dump.h" #include "svga_shader_op.h" @@ -413,6 +416,11 @@ dump_dstreg(struct sh_dstreg dstreg, static void dump_srcreg( struct sh_srcreg srcreg, struct sh_srcreg *indreg, const struct dump_info *di ) { + struct sh_reg srcreg_sh = {0}; + /* bit-fields carefully aligned, ensure they stay that way. */ + STATIC_ASSERT(sizeof(struct sh_reg) == sizeof(struct sh_srcreg)); + memcpy(&srcreg_sh, &srcreg, sizeof(srcreg_sh)); + switch (srcreg.modifier) { case SVGA3DSRCMOD_NEG: case SVGA3DSRCMOD_BIASNEG: @@ -427,7 +435,7 @@ static void dump_srcreg( struct sh_srcreg srcreg, struct sh_srcreg *indreg, cons case SVGA3DSRCMOD_NOT: _debug_printf( "!" ); } - dump_reg( *(struct sh_reg *) &srcreg, indreg, di ); + dump_reg(srcreg_sh, indreg, di ); switch (srcreg.modifier) { case SVGA3DSRCMOD_NONE: case SVGA3DSRCMOD_NEG: |