Message ID | 9f6f8888-4dc1-a6b0-0590-35fc8a276369@suse.com |
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State | Accepted |
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Series |
x86: drop bogus Tbyte
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Checks
Context | Check | Description |
---|---|---|
snail/binutils-gdb-check | success | Github commit url |
Commit Message
Jan Beulich
Oct. 31, 2022, 10:18 a.m. UTC
Prior to commit 1cb0ab18ad24 ("x86/Intel: restrict suffix derivation") the Tbyte modifier on the FLDT and FSTPT templates was pointless, as No_ldSuf would have prevented it being accepted. Due to the special nature of LONG_DOUBLE_MNEM_SUFFIX said commit, however, has led to these insns being accepted in Intel syntax mode even when "tbyte ptr" was present. Restore original behavior by dropping Tbyte there. (Note that these insns in principle should by marked AT&T syntax only, but since they haven't been so far we probably shouldn't change that.)
Comments
On Mon, Oct 31, 2022 at 3:18 AM Jan Beulich <jbeulich@suse.com> wrote: > > Prior to commit 1cb0ab18ad24 ("x86/Intel: restrict suffix derivation") > the Tbyte modifier on the FLDT and FSTPT templates was pointless, as > No_ldSuf would have prevented it being accepted. Due to the special > nature of LONG_DOUBLE_MNEM_SUFFIX said commit, however, has led to these > insns being accepted in Intel syntax mode even when "tbyte ptr" was > present. Restore original behavior by dropping Tbyte there. (Note that > these insns in principle should by marked AT&T syntax only, but since > they haven't been so far we probably shouldn't change that.) > > --- a/opcodes/i386-opc.tbl > +++ b/opcodes/i386-opc.tbl > @@ -599,7 +599,7 @@ fld, 0xdb, 5, CpuFP, Modrm|No_bSuf|No_wS > fild, 0xdf, 0, CpuFP, Modrm|FloatMF|No_bSuf|No_wSuf|No_qSuf|No_ldSuf, { Word|Dword|Unspecified|BaseIndex } > fild, 0xdf, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_ldSuf|NoRex64, { Qword|Unspecified|BaseIndex } > fildll, 0xdf, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|ATTSyntax, { Unspecified|BaseIndex } > -fldt, 0xdb, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Tbyte|Unspecified|BaseIndex } > +fldt, 0xdb, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Unspecified|BaseIndex } > fbld, 0xdf, 4, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf, { Tbyte|Unspecified|BaseIndex } > > // store (no pop) > @@ -617,7 +617,7 @@ fstp, 0xdb, 7, CpuFP, Modrm|No_bSuf|No_w > fistp, 0xdf, 3, CpuFP, Modrm|FloatMF|No_bSuf|No_wSuf|No_qSuf|No_ldSuf, { Word|Dword|Unspecified|BaseIndex } > fistp, 0xdf, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_ldSuf|NoRex64, { Qword|Unspecified|BaseIndex } > fistpll, 0xdf, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|ATTSyntax, { Unspecified|BaseIndex } > -fstpt, 0xdb, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Tbyte|Unspecified|BaseIndex } > +fstpt, 0xdb, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Unspecified|BaseIndex } > fbstp, 0xdf, 6, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf, { Tbyte|Unspecified|BaseIndex } > > // exchange %st<n> with %st0 OK. Thanks.
--- a/opcodes/i386-opc.tbl +++ b/opcodes/i386-opc.tbl @@ -599,7 +599,7 @@ fld, 0xdb, 5, CpuFP, Modrm|No_bSuf|No_wS fild, 0xdf, 0, CpuFP, Modrm|FloatMF|No_bSuf|No_wSuf|No_qSuf|No_ldSuf, { Word|Dword|Unspecified|BaseIndex } fild, 0xdf, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_ldSuf|NoRex64, { Qword|Unspecified|BaseIndex } fildll, 0xdf, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|ATTSyntax, { Unspecified|BaseIndex } -fldt, 0xdb, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Tbyte|Unspecified|BaseIndex } +fldt, 0xdb, 5, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Unspecified|BaseIndex } fbld, 0xdf, 4, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf, { Tbyte|Unspecified|BaseIndex } // store (no pop) @@ -617,7 +617,7 @@ fstp, 0xdb, 7, CpuFP, Modrm|No_bSuf|No_w fistp, 0xdf, 3, CpuFP, Modrm|FloatMF|No_bSuf|No_wSuf|No_qSuf|No_ldSuf, { Word|Dword|Unspecified|BaseIndex } fistp, 0xdf, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_ldSuf|NoRex64, { Qword|Unspecified|BaseIndex } fistpll, 0xdf, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|ATTSyntax, { Unspecified|BaseIndex } -fstpt, 0xdb, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Tbyte|Unspecified|BaseIndex } +fstpt, 0xdb, 7, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Unspecified|BaseIndex } fbstp, 0xdf, 6, CpuFP, Modrm|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf, { Tbyte|Unspecified|BaseIndex } // exchange %st<n> with %st0