On Mon, Mar 5, 2012 at 4:53 AM, H.J. Lu <hjl.to...@gmail.com> wrote: > and compiler does generate the same output. i386.c also has > > xasm = "jmp\t%A0"; > xasm = "call\t%A0"; > > for calls. There are no separate indirect call patterns. For x32, > only indirect register calls have to be in DImode. The direct call > should be in Pmode (SImode).
Direct call just expects label to some abolute address that is assumed to fit in 32 bits (see constant_call_address_operand_p). call and jmp insn expect word_mode operands, so please change ix86_expand_call and call patterns in the same way as jump instructions above. > Since x86-64 hardware always zero-extends upper 32bits of 64bit > registers when loading its lower 32bits, it is safe and easier to just > to output 64bit registers for %A than zero-extend it by hand for all > jump/call patterns. No, the instruction expects word_mode operands, so we have to extend values to expected mode. I don't think that patching at insn output time is acceptable. BTW: I propose to split the patch into smaller pieces, dealing with various independent parts separately. Handling jump/call insn is definitely one of them, the other is stringops handling, another prologue/epilogue expansion. Uros.
