diff options
3 files changed, 208 insertions, 1 deletions
diff --git a/toolchain/musl/common.mk b/toolchain/musl/common.mk index 433ca2167e..bb93b7b28d 100644 --- a/toolchain/musl/common.mk +++ b/toolchain/musl/common.mk @@ -9,7 +9,7 @@ include $(INCLUDE_DIR)/target.mk PKG_NAME:=musl PKG_VERSION:=1.1.23 -PKG_RELEASE:=2 +PKG_RELEASE:=3 PKG_SOURCE_PROTO:=git PKG_SOURCE_SUBDIR:=$(PKG_NAME)-$(PKG_VERSION) diff --git a/toolchain/musl/patches/030-fix-x87-stack-imbalance-in-corner-cases-of-i386-math.patch b/toolchain/musl/patches/030-fix-x87-stack-imbalance-in-corner-cases-of-i386-math.patch new file mode 100644 index 0000000000..a709330079 --- /dev/null +++ b/toolchain/musl/patches/030-fix-x87-stack-imbalance-in-corner-cases-of-i386-math.patch @@ -0,0 +1,179 @@ +From f3ed8bfe8a82af1870ddc8696ed4cc1d5aa6b441 Mon Sep 17 00:00:00 2001 +From: Rich Felker <dalias@aerifal.cx> +Date: Mon, 5 Aug 2019 18:41:47 -0400 +Subject: fix x87 stack imbalance in corner cases of i386 math asm + +commit 31c5fb80b9eae86f801be4f46025bc6532a554c5 introduced underflow +code paths for the i386 math asm, along with checks on the fpu status +word to skip the underflow-generation instructions if the underflow +flag was already raised. unfortunately, at least one such path, in +log1p, returned with 2 items on the x87 stack rather than just 1 item +for the return value. this is a violation of the ABI's calling +convention, and could cause subsequent floating point code to produce +NANs due to x87 stack overflow. if floating point results are used in +flow control, this can lead to runaway wrong code execution. + +rather than reviewing each "underflow already raised" code path for +correctness, remove them all. they're likely slower than just +performing the underflow code unconditionally, and significantly more +complex. + +all of this code should be ripped out and replaced by C source files +with inline asm. doing so would preclude this kind of error by having +the compiler perform all x87 stack register allocation and stack +manipulation, and would produce comparable or better code. however +such a change is a much larger project. +--- + src/math/i386/asin.s | 10 ++-------- + src/math/i386/atan.s | 7 ++----- + src/math/i386/atan2.s | 5 +---- + src/math/i386/atan2f.s | 5 +---- + src/math/i386/atanf.s | 7 ++----- + src/math/i386/exp.s | 10 ++-------- + src/math/i386/log1p.s | 7 ++----- + src/math/i386/log1pf.s | 7 ++----- + 8 files changed, 14 insertions(+), 44 deletions(-) + +--- a/src/math/i386/asin.s ++++ b/src/math/i386/asin.s +@@ -7,13 +7,10 @@ asinf: + cmp $0x01000000,%eax + jae 1f + # subnormal x, return x with underflow +- fnstsw %ax +- and $16,%ax +- jnz 2f + fld %st(0) + fmul %st(1) + fstps 4(%esp) +-2: ret ++ ret + + .global asinl + .type asinl,@function +@@ -30,11 +27,8 @@ asin: + cmp $0x00200000,%eax + jae 1f + # subnormal x, return x with underflow +- fnstsw %ax +- and $16,%ax +- jnz 2f + fsts 4(%esp) +-2: ret ++ ret + 1: fld %st(0) + fld1 + fsub %st(0),%st(1) +--- a/src/math/i386/atan.s ++++ b/src/math/i386/atan.s +@@ -10,8 +10,5 @@ atan: + fpatan + ret + # subnormal x, return x with underflow +-1: fnstsw %ax +- and $16,%ax +- jnz 2f +- fsts 4(%esp) +-2: ret ++1: fsts 4(%esp) ++ ret +--- a/src/math/i386/atan2.s ++++ b/src/math/i386/atan2.s +@@ -10,8 +10,5 @@ atan2: + cmp $0x00200000,%eax + jae 1f + # subnormal x, return x with underflow +- fnstsw %ax +- and $16,%ax +- jnz 1f + fsts 4(%esp) +-1: ret ++ ret +--- a/src/math/i386/atan2f.s ++++ b/src/math/i386/atan2f.s +@@ -10,10 +10,7 @@ atan2f: + cmp $0x01000000,%eax + jae 1f + # subnormal x, return x with underflow +- fnstsw %ax +- and $16,%ax +- jnz 1f + fld %st(0) + fmul %st(1) + fstps 4(%esp) +-1: ret ++ ret +--- a/src/math/i386/atanf.s ++++ b/src/math/i386/atanf.s +@@ -10,10 +10,7 @@ atanf: + fpatan + ret + # subnormal x, return x with underflow +-1: fnstsw %ax +- and $16,%ax +- jnz 2f +- fld %st(0) ++1: fld %st(0) + fmul %st(1) + fstps 4(%esp) +-2: ret ++ ret +--- a/src/math/i386/exp.s ++++ b/src/math/i386/exp.s +@@ -7,13 +7,10 @@ expm1f: + cmp $0x01000000,%eax + jae 1f + # subnormal x, return x with underflow +- fnstsw %ax +- and $16,%ax +- jnz 2f + fld %st(0) + fmul %st(1) + fstps 4(%esp) +-2: ret ++ ret + + .global expm1l + .type expm1l,@function +@@ -30,11 +27,8 @@ expm1: + cmp $0x00200000,%eax + jae 1f + # subnormal x, return x with underflow +- fnstsw %ax +- and $16,%ax +- jnz 2f + fsts 4(%esp) +-2: ret ++ ret + 1: fldl2e + fmulp + mov $0xc2820000,%eax +--- a/src/math/i386/log1p.s ++++ b/src/math/i386/log1p.s +@@ -16,9 +16,6 @@ log1p: + fyl2x + ret + # subnormal x, return x with underflow +-2: fnstsw %ax +- and $16,%ax +- jnz 1f +- fsts 4(%esp) ++2: fsts 4(%esp) + fstp %st(1) +-1: ret ++ ret +--- a/src/math/i386/log1pf.s ++++ b/src/math/i386/log1pf.s +@@ -16,10 +16,7 @@ log1pf: + fyl2x + ret + # subnormal x, return x with underflow +-2: fnstsw %ax +- and $16,%ax +- jnz 1f +- fxch ++2: fxch + fmul %st(1) + fstps 4(%esp) +-1: ret ++ ret diff --git a/toolchain/musl/patches/031-fix-build-regression-in-i386-asm-for-atan2-atan2f.patch b/toolchain/musl/patches/031-fix-build-regression-in-i386-asm-for-atan2-atan2f.patch new file mode 100644 index 0000000000..8c5161b52c --- /dev/null +++ b/toolchain/musl/patches/031-fix-build-regression-in-i386-asm-for-atan2-atan2f.patch @@ -0,0 +1,28 @@ +From 6818c31c9bc4bbad5357f1de14bedf781e5b349e Mon Sep 17 00:00:00 2001 +From: Rich Felker <dalias@aerifal.cx> +Date: Mon, 5 Aug 2019 19:57:07 -0400 +Subject: fix build regression in i386 asm for atan2, atan2f + +commit f3ed8bfe8a82af1870ddc8696ed4cc1d5aa6b441 inadvertently removed +labels that were still needed. +--- + src/math/i386/atan2.s | 2 +- + src/math/i386/atan2f.s | 2 +- + 2 files changed, 2 insertions(+), 2 deletions(-) + +--- a/src/math/i386/atan2.s ++++ b/src/math/i386/atan2.s +@@ -11,4 +11,4 @@ atan2: + jae 1f + # subnormal x, return x with underflow + fsts 4(%esp) +- ret ++1: ret +--- a/src/math/i386/atan2f.s ++++ b/src/math/i386/atan2f.s +@@ -13,4 +13,4 @@ atan2f: + fld %st(0) + fmul %st(1) + fstps 4(%esp) +- ret ++1: ret |