Patchwork [4/6] tcg-hppa: Schedule the address masking after the TLB load.

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Submitter Richard Henderson
Date April 9, 2010, 5:49 p.m.
Message ID <b692abef5eb6dadf37e20cb76f79ead71cd51869.1271253049.git.rth@twiddle.net>
Download mbox | patch
Permalink /patch/50158/
State New
Headers show

Comments

Richard Henderson - April 9, 2010, 5:49 p.m.
Issue the tlb load as early as possible and perform the address
masking while the load is completing.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 tcg/hppa/tcg-target.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

Patch

diff --git a/tcg/hppa/tcg-target.c b/tcg/hppa/tcg-target.c
index 2f3b770..6941e22 100644
--- a/tcg/hppa/tcg-target.c
+++ b/tcg/hppa/tcg-target.c
@@ -904,7 +904,6 @@  static int tcg_out_tlb_read(TCGContext *s, int r0, int r1, int addrlo,
        CPU_TLB_ENTRY_BITS is > 3, so we can't merge that shift with the
        add that follows.  */
     tcg_out_extr(s, r1, addrlo, TARGET_PAGE_BITS, CPU_TLB_BITS, 0);
-    tcg_out_andi(s, r0, addrlo, TARGET_PAGE_MASK | ((1 << s_bits) - 1));
     tcg_out_shli(s, r1, r1, CPU_TLB_ENTRY_BITS);
     tcg_out_arith(s, r1, r1, TCG_AREG0, INSN_ADDL);
 
@@ -927,6 +926,12 @@  static int tcg_out_tlb_read(TCGContext *s, int r0, int r1, int addrlo,
         tcg_out_ld(s, TCG_TYPE_PTR, TCG_REG_R20, r1, offset);
     }
 
+    /* Compute the value that ought to appear in the TLB for a hit, namely, the page
+       of the address.  We include the low N bits of the address to catch unaligned
+       accesses and force them onto the slow path.  Do this computation after having
+       issued the load from the TLB slot to give the load time to complete.  */
+    tcg_out_andi(s, r0, addrlo, TARGET_PAGE_MASK | ((1 << s_bits) - 1));
+
     /* If not equal, jump to lab_miss. */
     if (TARGET_LONG_BITS == 64) {
         tcg_out_brcond2(s, TCG_COND_NE, TCG_REG_R20, TCG_REG_R23,