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[powerpc] fix movdf_hardfloat32 pattern
- From: Nathan Sidwell <nathan at codesourcery dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: David Edelsohn <edelsohn at us dot ibm dot com>
- Date: Fri, 15 Dec 2006 09:59:13 +0000
- Subject: [powerpc] fix movdf_hardfloat32 pattern
This patch fixes a bug I found in a 3.4 toolchain. The bug is still present in
mainline, but the testcase I have doesn't tickle the problematic sequence.
This testcase has a massive structure, such that the byte offset to the double
member is 0x297ff8 bytes. We construct a sequence that ends with,
(insn:TI 13 11 32 0 (set (mem/s:DF (plus:SI (reg/f:SI 11 11 [121])
(const_int 32760 [0x7ff8])) [7 <variable>.member+0 S8 A64])
(reg:DF 9 9 [122])) 311 {*movdf_hardfloat32}
Because of rs6000_mode_dependent_address we do not consider the 0x7ff8' addend
to be an offsettable address. Hence the the output pattern of case 2: uses the
second alternative of stx/cal/stx/cal sequence. but here, we've not got an
indexable address so the assembler barfs. the load patterns have the same problem.
The obvious fix is to use %X output format to append the 'x' as necessary.
I'm not sure if it's worth committing the testcase, given it no longer generates
this code.
Tested on powerpc-wrs-vxworks, ok?
nathan
--
Nathan Sidwell :: http://www.codesourcery.com :: CodeSourcery
nathan@codesourcery.com :: http://www.planetfall.pwp.blueyonder.co.uk
2006-12-15 Nathan Sidwell <nathan@codesourcery.com>
* config/rs6000/rs6000.md (*movdf_hardfloat32): Use %X format to
determine if memory operand is an indexed address or not.
Index: config/rs6000/rs6000.md
===================================================================
--- config/rs6000/rs6000.md (revision 119362)
+++ config/rs6000/rs6000.md (working copy)
@@ -8359,15 +8359,15 @@
operands[1], 0))
{
output_asm_insn (\"{cal|la} %0,4(%0)\", &addreg);
- output_asm_insn (\"{lx|lwzx} %L0,%1\", operands);
+ output_asm_insn (\"{l|lwz}%X1 %L0,%1\", operands);
output_asm_insn (\"{cal|la} %0,-4(%0)\", &addreg);
- return \"{lx|lwzx} %0,%1\";
+ return \"{l|lwz}%X1 %0,%1\";
}
else
{
- output_asm_insn (\"{lx|lwzx} %0,%1\", operands);
+ output_asm_insn (\"{l|lwz}%X1 %0,%1\", operands);
output_asm_insn (\"{cal|la} %0,4(%0)\", &addreg);
- output_asm_insn (\"{lx|lwzx} %L0,%1\", operands);
+ output_asm_insn (\"{l|lwz}%X1 %L0,%1\", operands);
output_asm_insn (\"{cal|la} %0,-4(%0)\", &addreg);
return \"\";
}
@@ -8384,9 +8384,9 @@
rtx addreg;
addreg = find_addr_reg (XEXP (operands[0], 0));
- output_asm_insn (\"{stx|stwx} %1,%0\", operands);
+ output_asm_insn (\"{st|stw}%X0 %1,%0\", operands);
output_asm_insn (\"{cal|la} %0,4(%0)\", &addreg);
- output_asm_insn (\"{stx|stwx} %L1,%0\", operands);
+ output_asm_insn (\"{st|stw}%X0 %L1,%0\", operands);
output_asm_insn (\"{cal|la} %0,-4(%0)\", &addreg);
return \"\";
}
struct Bar
{
int pad[679933];
double member;
};
extern struct Bar *ptr;
void Foo (void)
{
ptr->member = 5.0;
}