On Sat, 2022-04-09 at 14:05 -0400, Antoni Boucher wrote: > Here's the updated patch.
Thanks. I updated the patch somewhat: * fixed up some hunks that didn't quite apply * whitespace fixes * added a missing comment * regenerated .texinfo from .rst * test-bitcast.c failed for me; the bitcast of -5.1298714 float to int didn't give me the expected 35569201; I got this value: (gdb) p val $1 = -1062983704 (gdb) p /x val $2 = 0xc0a427e8 (gdb) p /x 35569201 $3 = 0x21ebe31 and I couldn't figure out what the relationship between these two values could be. The expected: 35569201 == 0x21ebe31 0x021ebe31 as float is 1 × 2^-123 × 1.2401792 = 1.1662589e-37 I rewrote the test to explicitly use int32_t rather than int, but this didn't help. I wondered if this was an endianness issue, but: -5.1298713 is -1 × 2^2 × 1.2824678, which is 0xc0a427e8 In the end, I changed the constants in the test to these: (gdb) p *(float *)&val $25 = 3.14159274 (gdb) p *(int32_t *)&val $26 = 1078530011 (gdb) p /x *(int32_t *)&val $27 = 0x40490fdb which passes for me. Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu. I've pushed the patch to trunk for GCC 12 as r12-8117-g30f7c83e9cfe7c https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=30f7c83e9cfe7c015448d72f63c4c39d14bc6de6 Dave > > On Fri, 2022-04-08 at 15:22 -0400, David Malcolm wrote: > > On Fri, 2022-01-21 at 18:41 -0500, Antoni Boucher wrote: > > > Hi. > > > Here's the updated patch. > > > > > > > Thanks. Review below: > > > > [...snip...] > > > > > diff --git a/gcc/jit/libgccjit.cc b/gcc/jit/libgccjit.cc > > > index 4c352e8c93d..6bf1e1ceee0 100644 > > > --- a/gcc/jit/libgccjit.cc > > > +++ b/gcc/jit/libgccjit.cc > > > @@ -2405,6 +2405,34 @@ gcc_jit_context_new_cast (gcc_jit_context > > > *ctxt, > > > return static_cast <gcc_jit_rvalue *> (ctxt->new_cast (loc, > > > rvalue, type)); > > > } > > > > > > +/* Public entrypoint. See description in libgccjit.h. > > > + > > > + After error-checking, the real work is done by the > > > + gcc::jit::recording::context::new_bitcast method in jit- > > > recording.c. */ > > > + > > > +gcc_jit_rvalue * > > > +gcc_jit_context_new_bitcast (gcc_jit_context *ctxt, > > > + gcc_jit_location *loc, > > > + gcc_jit_rvalue *rvalue, > > > + gcc_jit_type *type) > > > +{ > > > + RETURN_NULL_IF_FAIL (ctxt, NULL, loc, "NULL context"); > > > + JIT_LOG_FUNC (ctxt->get_logger ()); > > > + /* LOC can be NULL. */ > > > + RETURN_NULL_IF_FAIL (rvalue, ctxt, loc, "NULL rvalue"); > > > + RETURN_NULL_IF_FAIL (type, ctxt, loc, "NULL type"); > > > + // TODO: check the sizes. > > > + /*RETURN_NULL_IF_FAIL_PRINTF3 ( > > > + is_valid_cast (rvalue->get_type (), type), > > > + ctxt, loc, > > > + "cannot cast %s from type: %s to type: %s", > > > + rvalue->get_debug_string (), > > > + rvalue->get_type ()->get_debug_string (), > > > + type->get_debug_string ());*/ > > > > I think we agreed that we can't check the sizes at this point, so > > this > > commented-out check would be better replaced with a comment > > explaining > > that we have to defer the check to playback time, when we have the > > trees. > > > > > + > > > + return static_cast <gcc_jit_rvalue *> (ctxt->new_bitcast (loc, > > > rvalue, type)); > > > +} > > > + > > > /* Public entrypoint. See description in libgccjit.h. > > > > > > After error-checking, the real work is done by the > > > > [...snip...] > > > > > diff --git a/gcc/testsuite/jit.dg/test-bitcast.c > > > b/gcc/testsuite/jit.dg/test-bitcast.c > > > new file mode 100644 > > > index 00000000000..a092fa117e6 > > > --- /dev/null > > > +++ b/gcc/testsuite/jit.dg/test-bitcast.c > > > @@ -0,0 +1,60 @@ > > > +#include <stdlib.h> > > > +#include <stdio.h> > > > +#include <string.h> > > > + > > > +#include "libgccjit.h" > > > + > > > +#include "harness.h" > > > + > > > +void > > > +create_code (gcc_jit_context *ctxt, void *user_data) > > > +{ > > > + /* Let's try to inject the equivalent of: > > > +int > > > +my_bitcast (double x) > > > +{ > > > + return bitcast(x, int); > > > +} > > > + */ > > > + gcc_jit_type *int_type = > > > + gcc_jit_context_get_int_type (ctxt, 4, 1); > > > + gcc_jit_type *float_type = > > > + gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_FLOAT); > > > > This uses GCC_JIT_TYPE_FLOAT for the param... > > > > > + > > > + gcc_jit_param *x = > > > + gcc_jit_context_new_param ( > > > + ctxt, > > > + NULL, > > > + float_type, "x"); > > > + gcc_jit_param *params[1] = {x}; > > > + gcc_jit_function *func = > > > + gcc_jit_context_new_function (ctxt, > > > + NULL, > > > + GCC_JIT_FUNCTION_EXPORTED, > > > + int_type, > > > + "my_bitcast", > > > + 1, params, 0); > > > > [..snip...] > > > > > + > > > +void > > > +verify_code (gcc_jit_context *ctxt, gcc_jit_result *result) > > > +{ > > > + typedef int (*my_bitcast_fn_type) (double); > > > > ...but this uses "double". Presumably these should agree, and have > > the > > same sizeof as the integer type. > > > > > + CHECK_NON_NULL (result); > > > + my_bitcast_fn_type my_bitcast = > > > + (my_bitcast_fn_type)gcc_jit_result_get_code (result, > > > "my_bitcast"); > > > + CHECK_NON_NULL (my_bitcast); > > > + int val = my_bitcast (-5.1298714); > > > + note ("my_bitcast returned: %d", val); > > > + CHECK_VALUE (val, 35569201); > > > > Out of curiosity, is there any particular significance for these > > values? FWIW I rather like: > > http://evanw.github.io/float-toy/ > > for directly manipulating the bits of floating point numbers. > > The given float values, when bitcast to an int, gives the given int > value. > > > > > > > [...snip...] > > > > > diff --git a/gcc/toplev.cc b/gcc/toplev.cc > > > index 534da1462e8..bc4921974eb 100644 > > > --- a/gcc/toplev.cc > > > +++ b/gcc/toplev.cc > > > @@ -2368,6 +2368,7 @@ toplev::finalize (void) > > > gcse_c_finalize (); > > > ipa_cp_c_finalize (); > > > ira_costs_c_finalize (); > > > + tree_cc_finalize (); > > > > > > /* save_decoded_options uses opts_obstack, so these must > > > be cleaned up together. */ > > > diff --git a/gcc/tree.cc b/gcc/tree.cc > > > index ae159ee20ce..fe9d9083026 100644 > > > --- a/gcc/tree.cc > > > +++ b/gcc/tree.cc > > > @@ -6963,6 +6963,15 @@ build_reference_type (tree to_type) > > > (HOST_BITS_PER_WIDE_INT > 64 ? HOST_BITS_PER_WIDE_INT : 64) > > > static GTY(()) tree nonstandard_integer_type_cache[2 * > > > MAX_INT_CACHED_PREC + 2]; > > > > > > +static void > > > +clear_nonstandard_integer_type_cache (void) > > > +{ > > > + for (size_t i = 0 ; i < 2 * MAX_INT_CACHED_PREC + 2 ; i++) > > > + { > > > + nonstandard_integer_type_cache[i] = NULL; > > > + } > > > +} > > > + > > > /* Builds a signed or unsigned integer type of precision > > > PRECISION. > > > Used for C bitfields whose precision does not match that of > > > built-in target types. */ > > > @@ -14565,6 +14574,12 @@ get_attr_nonstring_decl (tree expr, tree > > > *ref) > > > return NULL_TREE; > > > } > > > > > > +void > > > +tree_cc_finalize (void) > > > +{ > > > + clear_nonstandard_integer_type_cache (); > > > +} > > > + > > > #if CHECKING_P > > > > > > namespace selftest { > > > diff --git a/gcc/tree.h b/gcc/tree.h > > > index 30bc53c2996..bf886fc2472 100644 > > > --- a/gcc/tree.h > > > +++ b/gcc/tree.h > > > @@ -5385,6 +5385,7 @@ extern bool real_minus_onep (const_tree); > > > extern void init_ttree (void); > > > extern void build_common_tree_nodes (bool); > > > extern void build_common_builtin_nodes (void); > > > +extern void tree_cc_finalize (void); > > > extern tree build_nonstandard_integer_type (unsigned > > > HOST_WIDE_INT, int); > > > extern tree build_nonstandard_boolean_type (unsigned > > > HOST_WIDE_INT); > > > extern tree build_range_type (tree, tree, tree); > > > > Looks OK to me, but am not officially a maintainer of these parts. > > > > LGTM with those nits fixed - for next stage 1, or for trunk now if > > the > > release maintainers are OK with it. > > > > Thanks again for the patch, and sorry about the belated review. > > > > Dave > > > > > > >