tcg: Support arbitrary size + alignment

Previously we allowed fully unaligned operations, but not operations
that are aligned but with less alignment than the operation size.

In addition, arm32, ia64, mips, and sparc had been omitted from the
previous overalignment patch, which would have led to that alignment
being enforced.

Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 7 insertions, 6 deletions

diff --git a/tcg/aarch64/tcg-target.inc.c b/tcg/aarch64/tcg-target.inc.c
index 08b2d031aa..c8374b864f 100644
--- a/tcg/aarch64/tcg-target.inc.c
+++ b/tcg/aarch64/tcg-target.inc.c
@@ -1081,23 +1081,24 @@ static void tcg_out_tlb_read(TCGContext *s, TCGReg addr_reg, TCGMemOp opc,
     int tlb_offset = is_read ?
         offsetof(CPUArchState, tlb_table[mem_index][0].addr_read)
         : offsetof(CPUArchState, tlb_table[mem_index][0].addr_write);
-    int a_bits = get_alignment_bits(opc);
+    unsigned a_bits = get_alignment_bits(opc);
+    unsigned s_bits = opc & MO_SIZE;
+    unsigned a_mask = (1u << a_bits) - 1;
+    unsigned s_mask = (1u << s_bits) - 1;
     TCGReg base = TCG_AREG0, x3;
     uint64_t tlb_mask;
 
     /* For aligned accesses, we check the first byte and include the alignment
        bits within the address.  For unaligned access, we check that we don't
        cross pages using the address of the last byte of the access.  */
-    if (a_bits >= 0) {
-        /* A byte access or an alignment check required */
-        tlb_mask = TARGET_PAGE_MASK | ((1 << a_bits) - 1);
+    if (a_bits >= s_bits) {
         x3 = addr_reg;
     } else {
         tcg_out_insn(s, 3401, ADDI, TARGET_LONG_BITS == 64,
-                     TCG_REG_X3, addr_reg, (1 << (opc & MO_SIZE)) - 1);
-        tlb_mask = TARGET_PAGE_MASK;
+                     TCG_REG_X3, addr_reg, s_mask - a_mask);
         x3 = TCG_REG_X3;
     }
+    tlb_mask = (uint64_t)TARGET_PAGE_MASK | a_mask;
 
     /* Extract the TLB index from the address into X0.
        X0<CPU_TLB_BITS:0> =