[V6,2/2] split complicate 64bit constant to memory for -m32 -mpowerpc64

Message ID 20240701062251.3080507-2-guojiufu@linux.ibm.com
State New
Headers
Series [V6,1/2] split complicate 64bit constant to memory |

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Commit Message

Jiufu Guo July 1, 2024, 6:22 a.m. UTC
  Hi,

For "-m32 -mpowerpc64", it is also ok to use fewer instruciton (p?ld)
to loading 64bit constant from memory. So, splitting the complicate 64bit
constant to constant pool should also work for this case.

Compare with previous version:
This version is using the new parameter to control what kind of complicate
constanst should be put into memory.

Bootstrap and regtest pass on ppc64{,le}.
Also no regression for "-m32 -mpowerpc64" variation on ppc64.
Is this ok for trunk?

BR,
Jeff(Jiufu) Guo

gcc/ChangeLog:

	* config/rs6000/rs6000.cc (rs6000_emit_set_const): Split constant to
	pool for "-m32 -mpowerpc64".

gcc/testsuite/ChangeLog:

	* gcc.target/powerpc/pr63281.c: Allow checking -m32.

---
 gcc/config/rs6000/rs6000.cc                | 21 +++++++++++++++++++--
 gcc/testsuite/gcc.target/powerpc/pr63281.c |  2 +-
 2 files changed, 20 insertions(+), 3 deletions(-)
  

Patch

diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
index ec384e87868..c785fb20b1b 100644
--- a/gcc/config/rs6000/rs6000.cc
+++ b/gcc/config/rs6000/rs6000.cc
@@ -10245,8 +10245,7 @@  rs6000_emit_set_const (rtx dest, rtx source)
 	 after RA when reusing the DEST register to build the value.  */
       else if ((can_create_pseudo_p () || base_reg_operand (dest, mode))
 	       && num_insns_constant (source, mode)
-		    > rs6000_min_insns_constant_in_pool
-	       && TARGET_64BIT)
+		    > rs6000_min_insns_constant_in_pool)
 	{
 	  rtx sym = force_const_mem (mode, source);
 	  if (TARGET_TOC && SYMBOL_REF_P (XEXP (sym, 0))
@@ -10256,6 +10255,24 @@  rs6000_emit_set_const (rtx dest, rtx source)
 	      sym = gen_const_mem (mode, toc);
 	      set_mem_alias_set (sym, get_TOC_alias_set ());
 	    }
+	  else if (TARGET_32BIT)
+	    {
+	      /* After RA, reuse 'DEST' reg.  */
+	      rtx addr = can_create_pseudo_p ()
+			   ? gen_reg_rtx (Pmode)
+			   : gen_rtx_REG (Pmode, REGNO (dest));
+	      rtx sym_ref = XEXP (sym, 0);
+	      if (flag_pic)
+		emit_move_insn (addr, sym_ref);
+	      else
+		{
+		  emit_move_insn (addr, gen_rtx_HIGH (Pmode, sym_ref));
+		  emit_move_insn (addr, gen_rtx_LO_SUM (Pmode, addr, sym_ref));
+		}
+	      rtx mem = gen_rtx_MEM (mode, addr);
+	      MEM_COPY_ATTRIBUTES (mem, sym);
+	      sym = mem;
+	    }
 
 	  emit_move_insn (dest, sym);
 	}
diff --git a/gcc/testsuite/gcc.target/powerpc/pr63281.c b/gcc/testsuite/gcc.target/powerpc/pr63281.c
index 9763a7181fc..16a93b78606 100644
--- a/gcc/testsuite/gcc.target/powerpc/pr63281.c
+++ b/gcc/testsuite/gcc.target/powerpc/pr63281.c
@@ -7,5 +7,5 @@  foo (unsigned long long *a)
   *a++ = 0x2351847027482577ULL;
 }
 
-/* { dg-final { scan-assembler-times {\mp?ld\M} 1 { target { lp64 } } } } */
+/* { dg-final { scan-assembler-times {\mp?ld\M} 1 { target { has_arch_ppc64 } } } } */