[Bug rtl-optimization/83377] Missed optimization (x86): Bit operations should be converted to arithmetic
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83377 --- Comment #3 from Vinay Kumar --- The below mentioned pattern match in match.pd generates the assembly code similar to subtraction. == diff --git a/gcc/match.pd b/gcc/match.pd index fbb4d6f..3cde6a6 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -925,6 +925,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (bit_and @0 integer_all_onesp) (non_lvalue @0)) +/*Fold (x & ~CST) into (x - CST)*/ +(simplify(bit_and:c @0 INTEGER_CST@1) +(if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))) + (minus @0 (negate @1 + /* x & x -> x, x | x -> x */ (for bitop (bit_and bit_ior) (simplify == Assembly generated is as follows: == test.o: file format elf64-x86-64 Disassembly of section .text: : 0: 48 83 ff fe cmp$0xfffe,%rdi 4: 74 04 je a 6: 48 8b 7f fd mov-0x3(%rdi),%rdi a: e9 00 00 00 00jmpq f f: 90nop 0010 : 10: 48 83 ff fe cmp$0xfffe,%rdi 14: 74 04 je 1a 16: 48 8b 7f fe mov-0x2(%rdi),%rdi 1a: e9 00 00 00 00jmpq 1f ==
[Bug rtl-optimization/83377] Missed optimization (x86): Bit operations should be converted to arithmetic
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83377 --- Comment #4 from Vinay Kumar --- Hi, Above mentioned patch does not work for the pattern "if( x & 2 ) y = (x & ~2UL)". >> Probably still easier to fix in combine / simplify-rtx. We are working as per your suggestion. Regards, Vinay
[Bug target/86947] Erroneous code generated with O2 and O3 for PPC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86947 --- Comment #3 from Vinay Kumar --- Created attachment 44572 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44572&action=edit Testcase t2.c
[Bug target/86947] Erroneous code generated with O2 and O3 for PPC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86947 Vinay Kumar changed: What|Removed |Added CC||vinay.m.engg at gmail dot com --- Comment #2 from Vinay Kumar --- Created attachment 44571 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44571&action=edit Testcase t1.c
[Bug target/86947] Erroneous code generated with O2 and O3 for PPC
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86947 --- Comment #4 from Vinay Kumar --- Hi Richard, Thanks for checking the bug. Please find attached the testcase that would exit with message "Should NOT BE here" on miscompilation. The behavior is same with other targets as well. We have checked it with latest X86 and Aarch64 targets. gcc t1.c t2.c -O2 -m64 -lm
[Bug target/85667] (x86_64) ms_abi rules aren't followed when returning short structs with float values
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85667 Vinay Kumar changed: What|Removed |Added CC||vinay.m.engg at gmail dot com --- Comment #1 from Vinay Kumar --- Hi, The current exists in latest trunk sources also. Please let me know is there any progress on this. Regards, Vinay
