| Message ID | 543633BD.9030004@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Thu, Oct 9, 2014 at 12:05 AM, Michael Collison <michael.collison@linaro.org> wrote: > > The CLZ_DEFINED_VALUE_AT_ZERO macro is harded to return 32. For the vector > intrinsic vclz this is incorrect and should return the value eight. The > CTZ_DEFINED_VALUE_AT_ZERO has the same issue. Do you have a testcase? I almost think you should have a testcase which causes the constant folding. Though I don't think there is constant folding of the vector clz/ctz happening. Thanks, Andrew > > Tested on arm-linux-gnueabihf, arm-linux-gnueabi. > > 2014-10-08 Michael Collison <michael.collison@linaro.com> > > * config/arm/arm.h (CLZ_DEFINED_VALUE_AT_ZERO) : Update > to support vector modes > (CTZ_DEFINED_VALUE_AT_ZERO): Ditto > > -- > Michael Collison > Linaro Toolchain Working Group > michael.collison@linaro.org >
Yes this problem was found with Christophe's neon intrinsic tests which are awaiting approval. The problem was found by passing a value of zero to the vclz vector intrinsic. On 10/09/2014 12:11 AM, Andrew Pinski wrote: > On Thu, Oct 9, 2014 at 12:05 AM, Michael Collison > <michael.collison@linaro.org> wrote: >> The CLZ_DEFINED_VALUE_AT_ZERO macro is harded to return 32. For the vector >> intrinsic vclz this is incorrect and should return the value eight. The >> CTZ_DEFINED_VALUE_AT_ZERO has the same issue. > > Do you have a testcase? I almost think you should have a testcase > which causes the constant folding. Though I don't think there is > constant folding of the vector clz/ctz happening. > > Thanks, > Andrew > >> Tested on arm-linux-gnueabihf, arm-linux-gnueabi. >> >> 2014-10-08 Michael Collison <michael.collison@linaro.com> >> >> * config/arm/arm.h (CLZ_DEFINED_VALUE_AT_ZERO) : Update >> to support vector modes >> (CTZ_DEFINED_VALUE_AT_ZERO): Ditto >> >> -- >> Michael Collison >> Linaro Toolchain Working Group >> michael.collison@linaro.org >>
On 09/10/14 08:05, Michael Collison wrote: > > The CLZ_DEFINED_VALUE_AT_ZERO macro is harded to return 32. For the > vector intrinsic vclz this is incorrect and should return the value > eight. The CTZ_DEFINED_VALUE_AT_ZERO has the same issue. > > Tested on arm-linux-gnueabihf, arm-linux-gnueabi. > > 2014-10-08 Michael Collison <michael.collison@linaro.com> > > * config/arm/arm.h (CLZ_DEFINED_VALUE_AT_ZERO) : Update > to support vector modes > (CTZ_DEFINED_VALUE_AT_ZERO): Ditto > Update comment? /* The arm5 clz instruction returns 32. */ Thanks, Tejas.
Tejas, You are correct. I will update the comment. On 10/9/2014 12:55 AM, Tejas Belagod wrote: > On 09/10/14 08:05, Michael Collison wrote: >> >> The CLZ_DEFINED_VALUE_AT_ZERO macro is harded to return 32. For the >> vector intrinsic vclz this is incorrect and should return the value >> eight. The CTZ_DEFINED_VALUE_AT_ZERO has the same issue. >> >> Tested on arm-linux-gnueabihf, arm-linux-gnueabi. >> >> 2014-10-08 Michael Collison <michael.collison@linaro.com> >> >> * config/arm/arm.h (CLZ_DEFINED_VALUE_AT_ZERO) : Update >> to support vector modes >> (CTZ_DEFINED_VALUE_AT_ZERO): Ditto >> > > Update comment? > > /* The arm5 clz instruction returns 32. */ > > > Thanks, > Tejas. >
--- ../../../../linaro-gcc4_9_git/gcc/config/arm/arm.h 2014-10-08 13:49:01.109819957 -0700 +++ arm.h 2014-10-08 13:56:19.509841175 -0700 @@ -2138,8 +2138,10 @@ extern int making_const_table; : reverse_condition (code)) /* The arm5 clz instruction returns 32. */ -#define CLZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) ((VALUE) = 32, 1) -#define CTZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) ((VALUE) = 32, 1) +#define CLZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) \ + ((VALUE) = GET_MODE_UNIT_BITSIZE (MODE)) +#define CTZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) \ + ((VALUE) = GET_MODE_UNIT_BITSIZE (MODE)) #define CC_STATUS_INIT \ do { cfun->machine->thumb1_cc_insn = NULL_RTX; } while (0)
The CLZ_DEFINED_VALUE_AT_ZERO macro is harded to return 32. For the vector intrinsic vclz this is incorrect and should return the value eight. The CTZ_DEFINED_VALUE_AT_ZERO has the same issue. Tested on arm-linux-gnueabihf, arm-linux-gnueabi. 2014-10-08 Michael Collison <michael.collison@linaro.com> * config/arm/arm.h (CLZ_DEFINED_VALUE_AT_ZERO) : Update to support vector modes (CTZ_DEFINED_VALUE_AT_ZERO): Ditto