On Sun, 21 Apr 2013 05:29:28 +0100 (BST) "Maciej W. Rozycki" <macro@xxxxxxxxxxxxxx> wrote: > > Hmm, nobody has replied, so just FYI such widening multiplication is > available in all 64-bit MIPS hardware and GCC has supported it since 4.4 > or mid 2008 (older versions used a libgcc __multi3 helper, not quite so > efficient as you can imagine). $ powerpc64-linux-gcc --version powerpc64-linux-gcc (GCC) 4.6.3 ... $ powerpc64-linux-gcc -O2 -c mulditi3.c $ powerpc64-linux-objdump -d -r mulditi3.o mulditi3.o: file format elf64-powerpc Disassembly of section .text: 0000000000000000 <.mulditi3>: 0: 7c 08 02 a6 mflr r0 4: 7c 86 23 78 mr r6,r4 8: 7c c5 fe 76 sradi r5,r6,63 c: f8 01 00 10 std r0,16(r1) 10: 7c 64 1b 78 mr r4,r3 14: f8 21 ff 91 stdu r1,-112(r1) 18: 7c 63 fe 76 sradi r3,r3,63 1c: 48 00 00 01 bl 1c <.mulditi3+0x1c> 1c: R_PPC64_REL24 __multi3 20: 60 00 00 00 nop 24: 38 21 00 70 addi r1,r1,112 28: e8 01 00 10 ld r0,16(r1) 2c: 7c 08 03 a6 mtlr r0 30: 4e 80 00 20 blr 34: 00 00 00 00 .long 0x0 38: 00 00 00 01 .long 0x1 3c: 80 00 00 00 lwz r0,0(0) $ i.e. for gcc 4.6.3, 64 bit powerpc calls out to __multi3 The same is true for sparc64. -- Cheers, Stephen Rothwell sfr@xxxxxxxxxxxxxxxx
Attachment:
pgpb7aP4US2e7.pgp
Description: PGP signature
