[PULL 12/48] tcg: Fold deposit with zero to and

Richard Henderson posted 48 patches 1 year, 3 months ago
Maintainers: Cameron Esfahani <dirty@apple.com>, Roman Bolshakov <rbolshakov@ddn.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Alexander Graf <agraf@csgraf.de>, Peter Maydell <peter.maydell@linaro.org>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, Marcelo Tosatti <mtosatti@redhat.com>, Laurent Vivier <laurent@vivier.eu>, Stafford Horne <shorne@gmail.com>, Daniel Henrique Barboza <danielhb413@gmail.com>, "Cédric Le Goater" <clg@kaod.org>, David Gibson <david@gibson.dropbear.id.au>, Greg Kurz <groug@kaod.org>, Nicholas Piggin <npiggin@gmail.com>, Palmer Dabbelt <palmer@dabbelt.com>, Alistair Francis <alistair.francis@wdc.com>, Bin Meng <bin.meng@windriver.com>, Weiwei Li <liweiwei@iscas.ac.cn>, Liu Zhiwei <zhiwei_liu@linux.alibaba.com>, Yoshinori Sato <ysato@users.sourceforge.jp>, Halil Pasic <pasic@linux.ibm.com>, Christian Borntraeger <borntraeger@linux.ibm.com>, Thomas Huth <thuth@redhat.com>, David Hildenbrand <david@redhat.com>, Ilya Leoshkevich <iii@linux.ibm.com>, Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>, Artyom Tarasenko <atar4qemu@gmail.com>, Bastian Koppelmann <kbastian@mail.uni-paderborn.de>, WANG Xuerui <git@xen0n.name>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Aurelien Jarno <aurelien@aurel32.net>, Huacai Chen <chenhuacai@kernel.org>, Jiaxun Yang <jiaxun.yang@flygoat.com>, Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>, Stefan Weil <sw@weilnetz.de>
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[PULL 12/48] tcg: Fold deposit with zero to and
Posted by Richard Henderson 1 year, 3 months ago
Inserting a zero into a value, or inserting a value
into zero at offset 0 may be implemented with AND.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/optimize.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/tcg/optimize.c b/tcg/optimize.c
index d2156367a3..bbd9bb64c6 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1279,6 +1279,8 @@ static bool fold_ctpop(OptContext *ctx, TCGOp *op)
 
 static bool fold_deposit(OptContext *ctx, TCGOp *op)
 {
+    TCGOpcode and_opc;
+
     if (arg_is_const(op->args[1]) && arg_is_const(op->args[2])) {
         uint64_t t1 = arg_info(op->args[1])->val;
         uint64_t t2 = arg_info(op->args[2])->val;
@@ -1287,6 +1289,41 @@ static bool fold_deposit(OptContext *ctx, TCGOp *op)
         return tcg_opt_gen_movi(ctx, op, op->args[0], t1);
     }
 
+    switch (ctx->type) {
+    case TCG_TYPE_I32:
+        and_opc = INDEX_op_and_i32;
+        break;
+    case TCG_TYPE_I64:
+        and_opc = INDEX_op_and_i64;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    /* Inserting a value into zero at offset 0. */
+    if (arg_is_const(op->args[1])
+        && arg_info(op->args[1])->val == 0
+        && op->args[3] == 0) {
+        uint64_t mask = MAKE_64BIT_MASK(0, op->args[4]);
+
+        op->opc = and_opc;
+        op->args[1] = op->args[2];
+        op->args[2] = temp_arg(tcg_constant_internal(ctx->type, mask));
+        ctx->z_mask = mask & arg_info(op->args[1])->z_mask;
+        return false;
+    }
+
+    /* Inserting zero into a value. */
+    if (arg_is_const(op->args[2])
+        && arg_info(op->args[2])->val == 0) {
+        uint64_t mask = deposit64(-1, op->args[3], op->args[4], 0);
+
+        op->opc = and_opc;
+        op->args[2] = temp_arg(tcg_constant_internal(ctx->type, mask));
+        ctx->z_mask = mask & arg_info(op->args[1])->z_mask;
+        return false;
+    }
+
     ctx->z_mask = deposit64(arg_info(op->args[1])->z_mask,
                             op->args[3], op->args[4],
                             arg_info(op->args[2])->z_mask);
-- 
2.34.1