arg is long int, so arg = (arg << 22) >> 22 makes the upper 22 bits of arg equal to bit 9 (or bit 41). But we then mask away all but bits 0-9, so this is entirely redundant.
Signed-off-by: Rasmus Villemoes linux@rasmusvillemoes.dk --- gcc seems to be smart enough to realize this - the generated code is the same. This is thus just a tiny cleanup.
drivers/gpu/drm/sti/sti_awg_utils.c | 4 ---- 1 file changed, 4 deletions(-)
diff --git a/drivers/gpu/drm/sti/sti_awg_utils.c b/drivers/gpu/drm/sti/sti_awg_utils.c index 6029a2e3db1d..00d0698be9d3 100644 --- a/drivers/gpu/drm/sti/sti_awg_utils.c +++ b/drivers/gpu/drm/sti/sti_awg_utils.c @@ -65,7 +65,6 @@ static int awg_generate_instr(enum opcode opcode,
mux = 0; data_enable = 0; - arg = (arg << 22) >> 22; arg &= (0x3ff); break; case REPEAT: @@ -77,14 +76,12 @@ static int awg_generate_instr(enum opcode opcode,
mux = 0; data_enable = 0; - arg = (arg << 22) >> 22; arg &= (0x3ff); break; case JUMP: mux = 0; data_enable = 0; arg |= 0x40; /* for jump instruction 7th bit is 1 */ - arg = (arg << 22) >> 22; arg &= 0x3ff; break; case STOP: @@ -94,7 +91,6 @@ static int awg_generate_instr(enum opcode opcode, case RPTSET: case RPLSET: case HOLD: - arg = (arg << 24) >> 24; arg &= (0x0ff); break; default:
Hi Rasmus,
Thanks for the patch. I will integrated it in the next pull request for the sti driver.
BR Vincent
On 10/16/2015 03:14 PM, Rasmus Villemoes wrote:
arg is long int, so arg = (arg << 22) >> 22 makes the upper 22 bits of arg equal to bit 9 (or bit 41). But we then mask away all but bits 0-9, so this is entirely redundant.
Signed-off-by: Rasmus Villemoes linux@rasmusvillemoes.dk
gcc seems to be smart enough to realize this - the generated code is the same. This is thus just a tiny cleanup.
drivers/gpu/drm/sti/sti_awg_utils.c | 4 ---- 1 file changed, 4 deletions(-)
diff --git a/drivers/gpu/drm/sti/sti_awg_utils.c b/drivers/gpu/drm/sti/sti_awg_utils.c index 6029a2e3db1d..00d0698be9d3 100644 --- a/drivers/gpu/drm/sti/sti_awg_utils.c +++ b/drivers/gpu/drm/sti/sti_awg_utils.c @@ -65,7 +65,6 @@ static int awg_generate_instr(enum opcode opcode,
mux = 0; data_enable = 0;
case REPEAT:arg = (arg << 22) >> 22; arg &= (0x3ff); break;
@@ -77,14 +76,12 @@ static int awg_generate_instr(enum opcode opcode,
mux = 0; data_enable = 0;
case JUMP: mux = 0; data_enable = 0; arg |= 0x40; /* for jump instruction 7th bit is 1 */arg = (arg << 22) >> 22; arg &= (0x3ff); break;
case STOP:arg = (arg << 22) >> 22; arg &= 0x3ff; break;
@@ -94,7 +91,6 @@ static int awg_generate_instr(enum opcode opcode, case RPTSET: case RPLSET: case HOLD:
default:arg = (arg << 24) >> 24; arg &= (0x0ff); break;
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