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[Qemu-devel] [PATCH 1/3] tcg: Mask shift quantities while folding
From: |
Richard Henderson |
Subject: |
[Qemu-devel] [PATCH 1/3] tcg: Mask shift quantities while folding |
Date: |
Tue, 18 Mar 2014 08:48:20 -0700 |
The TCG result would be undefined, but we can at least produce one
plausible result and avoid triggering the wrath of analysis tools.
Reported-by: Peter Maydell <address@hidden>
Signed-off-by: Richard Henderson <address@hidden>
---
tcg/optimize.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/tcg/optimize.c b/tcg/optimize.c
index 7777743..2fc6344 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -220,34 +220,34 @@ static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg
x, TCGArg y)
return x ^ y;
case INDEX_op_shl_i32:
- return (uint32_t)x << (uint32_t)y;
+ return (uint32_t)x << (y & 31);
case INDEX_op_shl_i64:
- return (uint64_t)x << (uint64_t)y;
+ return (uint64_t)x << (y & 63);
case INDEX_op_shr_i32:
- return (uint32_t)x >> (uint32_t)y;
+ return (uint32_t)x >> (y & 31);
case INDEX_op_shr_i64:
- return (uint64_t)x >> (uint64_t)y;
+ return (uint64_t)x >> (y & 63);
case INDEX_op_sar_i32:
- return (int32_t)x >> (int32_t)y;
+ return (int32_t)x >> (y & 31);
case INDEX_op_sar_i64:
- return (int64_t)x >> (int64_t)y;
+ return (int64_t)x >> (y & 63);
case INDEX_op_rotr_i32:
- return ror32(x, y);
+ return ror32(x, y & 31);
case INDEX_op_rotr_i64:
- return ror64(x, y);
+ return ror64(x, y & 63);
case INDEX_op_rotl_i32:
- return rol32(x, y);
+ return rol32(x, y & 31);
case INDEX_op_rotl_i64:
- return rol64(x, y);
+ return rol64(x, y & 63);
CASE_OP_32_64(not):
return ~x;
--
1.8.5.3