Tested by visual inspection of gimple dump of reproducer supplied by bug reporter [1], and via "make check-jit"; takes jit.sum from 8234 to 8289 passes.
Committed to trunk as r225248. [1] https://gcc.gnu.org/ml/jit/2015-q2/msg00134.html gcc/jit/ChangeLog: PR jit/66700 * jit-playback.c (jit_mark_addressable): New function. (gcc::jit::playback::lvalue::get_address): Call jit_mark_addressable on the underlying tree. gcc/testsuite/ChangeLog: PR jit/66700 * jit.dg/all-non-failing-tests.h: Add test-pr66700-observing-write-through-ptr.c. * jit.dg/test-pr66700-observing-write-through-ptr.c: New testcase. --- gcc/jit/jit-playback.c | 42 ++++++++ gcc/testsuite/jit.dg/all-non-failing-tests.h | 10 ++ .../test-pr66700-observing-write-through-ptr.c | 109 +++++++++++++++++++++ 3 files changed, 161 insertions(+) create mode 100644 gcc/testsuite/jit.dg/test-pr66700-observing-write-through-ptr.c diff --git a/gcc/jit/jit-playback.c b/gcc/jit/jit-playback.c index c9d7c8c..1fe1091 100644 --- a/gcc/jit/jit-playback.c +++ b/gcc/jit/jit-playback.c @@ -1164,6 +1164,47 @@ dereference (location *loc) return new lvalue (get_context (), datum); } +/* Mark EXP saying that we need to be able to take the + address of it; it should not be allocated in a register. + Compare with e.g. c/c-typeck.c: c_mark_addressable. */ + +static void +jit_mark_addressable (tree exp) +{ + tree x = exp; + + while (1) + switch (TREE_CODE (x)) + { + case COMPONENT_REF: + /* (we don't yet support bitfields) */ + /* fallthrough */ + case ADDR_EXPR: + case ARRAY_REF: + case REALPART_EXPR: + case IMAGPART_EXPR: + x = TREE_OPERAND (x, 0); + break; + + case COMPOUND_LITERAL_EXPR: + case CONSTRUCTOR: + TREE_ADDRESSABLE (x) = 1; + return; + + case VAR_DECL: + case CONST_DECL: + case PARM_DECL: + case RESULT_DECL: + /* (we don't have a concept of a "register" declaration) */ + /* fallthrough */ + case FUNCTION_DECL: + TREE_ADDRESSABLE (x) = 1; + /* fallthrough */ + default: + return; + } +} + /* Construct a playback::rvalue instance (wrapping a tree) for an address-lookup. */ @@ -1177,6 +1218,7 @@ get_address (location *loc) tree ptr = build1 (ADDR_EXPR, t_ptrtype, t_lvalue); if (loc) get_context ()->set_tree_location (ptr, loc); + jit_mark_addressable (t_lvalue); return new rvalue (get_context (), ptr); } diff --git a/gcc/testsuite/jit.dg/all-non-failing-tests.h b/gcc/testsuite/jit.dg/all-non-failing-tests.h index 36a6160..21ff428 100644 --- a/gcc/testsuite/jit.dg/all-non-failing-tests.h +++ b/gcc/testsuite/jit.dg/all-non-failing-tests.h @@ -154,6 +154,13 @@ #undef create_code #undef verify_code +/* test-pr66700-observing-write-through-ptr.c */ +#define create_code create_code_pr66700_observing_write_through_ptr +#define verify_code verify_code_pr66700_observing_write_through_ptr +#include "test-pr66700-observing-write-through-ptr.c" +#undef create_code +#undef verify_code + /* test-reading-struct.c */ #define create_code create_code_reading_struct #define verify_code verify_code_reading_struct @@ -279,6 +286,9 @@ const struct testcase testcases[] = { {"nested_loop", create_code_nested_loop, verify_code_nested_loop}, + {"pr66700_observing_write_through_ptr", + create_code_pr66700_observing_write_through_ptr, + verify_code_pr66700_observing_write_through_ptr}, {"reading_struct ", create_code_reading_struct , verify_code_reading_struct }, diff --git a/gcc/testsuite/jit.dg/test-pr66700-observing-write-through-ptr.c b/gcc/testsuite/jit.dg/test-pr66700-observing-write-through-ptr.c new file mode 100644 index 0000000..4ffbfac --- /dev/null +++ b/gcc/testsuite/jit.dg/test-pr66700-observing-write-through-ptr.c @@ -0,0 +1,109 @@ +/* Test of PR jit/66700. */ + +#include <stdlib.h> +#include <stdio.h> + +#include "libgccjit.h" + +#include "harness.h" + +#ifdef __cplusplus +extern "C" { +#endif + + extern void + write_back_through_ptr (double *d); + +#ifdef __cplusplus +} +#endif + +void +create_code (gcc_jit_context *ctxt, void *user_data) +{ + /* Let's try to inject the equivalent of: + + double + test_caller_of_write_back_through_ptr (void) + { + double d; + d = 4.0; + write_back_through_ptr (&d); + return d; + } + */ + gcc_jit_type *t_void = + gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_VOID); + gcc_jit_type *t_double = + gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_DOUBLE); + gcc_jit_type *t_ptr_to_double = + gcc_jit_type_get_pointer (t_double); + + /* Declare the imported function. */ + gcc_jit_param *params[1]; + params[0] = + gcc_jit_context_new_param (ctxt, NULL, t_ptr_to_double, "d"); + gcc_jit_function *called_fn = + gcc_jit_context_new_function (ctxt, NULL, + GCC_JIT_FUNCTION_IMPORTED, + t_void, + "write_back_through_ptr", + 1, params, + 0); + + /* Build the test_fn. */ + gcc_jit_function *test_fn = + gcc_jit_context_new_function (ctxt, NULL, + GCC_JIT_FUNCTION_EXPORTED, + t_double, + "test_caller_of_write_back_through_ptr", + 0, NULL, + 0); + gcc_jit_lvalue *d = + gcc_jit_function_new_local (test_fn, NULL, t_double, "d"); + + gcc_jit_block *block = gcc_jit_function_new_block (test_fn, NULL); + + /* "d = 0.0" */ + gcc_jit_block_add_assignment ( + block, NULL, d, + gcc_jit_context_new_rvalue_from_int (ctxt, t_double, 4)); + + /* "write_back_through_ptr (&d);" */ + gcc_jit_rvalue *args[1]; + args[0] = gcc_jit_lvalue_get_address (d, NULL); + gcc_jit_block_add_eval ( + block, NULL, + gcc_jit_context_new_call (ctxt, + NULL, + called_fn, + 1, args)); + gcc_jit_block_end_with_return (block, + NULL, + gcc_jit_lvalue_as_rvalue (d)); +} + +extern void +write_back_through_ptr (double *d) +{ + *d = 5.600000; +} + +void +verify_code (gcc_jit_context *ctxt, gcc_jit_result *result) +{ + typedef double (*fn_type) (void); + CHECK_NON_NULL (result); + + fn_type test_caller_of_write_back_through_ptr = + (fn_type)gcc_jit_result_get_code (result, + "test_caller_of_write_back_through_ptr"); + CHECK_NON_NULL (test_caller_of_write_back_through_ptr); + + /* Call the JIT-generated function. */ + double d = test_caller_of_write_back_through_ptr (); + + /* Verify that it correctly called "write_back_through_ptr". */ + CHECK_VALUE (d, 5.600000); +} + -- 1.8.5.3
