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[PATCH v2 47/48] tcg/optimize: Propagate sign info for bit counting


From: Richard Henderson
Subject: [PATCH v2 47/48] tcg/optimize: Propagate sign info for bit counting
Date: Thu, 7 Oct 2021 12:54:55 -0700

The results are generally 6 bit unsigned values, though
the count leading and trailing bits may produce any value
for a zero input.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/optimize.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 1c106bfbc3..678e7c1983 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1216,6 +1216,7 @@ static bool fold_count_zeros(OptContext *ctx, TCGOp *op)
         g_assert_not_reached();
     }
     ctx->z_mask = arg_info(op->args[2])->z_mask | z_mask;
+    ctx->s_mask = smask_from_zmask(z_mask);
 
     return false;
 }
@@ -1236,6 +1237,7 @@ static bool fold_ctpop(OptContext *ctx, TCGOp *op)
     default:
         g_assert_not_reached();
     }
+    ctx->s_mask = smask_from_zmask(ctx->z_mask);
     return false;
 }
 
-- 
2.25.1




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