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| author | Cyrill Gorcunov <gorcunov@gmail.com> | 2009-10-31 10:34:43 +0300 |
|---|---|---|
| committer | Cyrill Gorcunov <gorcunov@gmail.com> | 2009-10-31 10:35:11 +0300 |
| commit | 41208028ff52d190044ee7532bf14c5aca0f899a (patch) | |
| tree | 2418e92ba336b3ed09a11eea52adffb646321b47 /parser.c | |
| parent | 4ea846623aa7633ac010504b013cc1c73a5fc09a (diff) | |
| download | nasm-41208028ff52d190044ee7532bf14c5aca0f899a.tar.gz nasm-41208028ff52d190044ee7532bf14c5aca0f899a.tar.bz2 nasm-41208028ff52d190044ee7532bf14c5aca0f899a.zip | |
BR 2887108: Use overflow_ helper to catch inappropriate imm optimization
We should use overflow_ helpers before check if an immediate
operand fit a type range, otherwise we may loose high bits.
For example when we assemble the following instruction
imul eax,eax,0x10000
with -Ox passed we optimze it up to imm8 though it must be imm32.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Diffstat (limited to 'parser.c')
| -rw-r--r-- | parser.c | 17 |
1 files changed, 9 insertions, 8 deletions
@@ -855,11 +855,10 @@ restart_parse: result->oprs[operand].segment = NO_SEG; /* don't care again */ result->oprs[operand].wrt = NO_SEG; /* still don't care */ + /* Be optimistic */ if(optimizing >= 0 && !(result->oprs[operand].type & STRICT)) - { - /* Be optimistic */ result->oprs[operand].type |= SBYTE16 | SBYTE32 | SBYTE64; - } + } else if (is_reloc(value)) { /* it's immediate */ result->oprs[operand].type |= IMMEDIATE; result->oprs[operand].offset = reloc_value(value); @@ -874,12 +873,14 @@ restart_parse: int32_t v32 = (int32_t)v64; int16_t v16 = (int16_t)v32; - if (v64 >= -128 && v64 <= 127) + if (v64 >= -128 && v64 <= 127) result->oprs[operand].type |= SBYTE64; - if (v32 >= -128 && v32 <= 127) - result->oprs[operand].type |= SBYTE32; - if (v16 >= -128 && v16 <= 127) - result->oprs[operand].type |= SBYTE16; + if (!overflow_signed(v64, sizeof(v32))) + if (v32 >= -128 && v32 <= 127) + result->oprs[operand].type |= SBYTE32; + if (!overflow_signed(v64, sizeof(v16))) + if (v16 >= -128 && v16 <= 127) + result->oprs[operand].type |= SBYTE16; } } } else { /* it's a register */ |