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-rw-r--r--lib/builtins/i386/ashldi3.S5
-rw-r--r--lib/builtins/i386/ashrdi3.S15
-rw-r--r--lib/builtins/i386/chkstk.S5
-rw-r--r--lib/builtins/i386/chkstk2.S5
-rw-r--r--lib/builtins/i386/divdi3.S43
-rw-r--r--lib/builtins/i386/floatdidf.S5
-rw-r--r--lib/builtins/i386/floatdisf.S5
-rw-r--r--lib/builtins/i386/floatdixf.S5
-rw-r--r--lib/builtins/i386/floatundidf.S7
-rw-r--r--lib/builtins/i386/floatundisf.S9
-rw-r--r--lib/builtins/i386/floatundixf.S5
-rw-r--r--lib/builtins/i386/lshrdi3.S9
-rw-r--r--lib/builtins/i386/moddi3.S41
-rw-r--r--lib/builtins/i386/muldi3.S11
-rw-r--r--lib/builtins/i386/udivdi3.S29
-rw-r--r--lib/builtins/i386/umoddi3.S37
16 files changed, 125 insertions, 111 deletions
diff --git a/lib/builtins/i386/ashldi3.S b/lib/builtins/i386/ashldi3.S
index 6f05dcf74..7ba912692 100644
--- a/lib/builtins/i386/ashldi3.S
+++ b/lib/builtins/i386/ashldi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/ashrdi3.S b/lib/builtins/i386/ashrdi3.S
index 206369f36..3cca4782a 100644
--- a/lib/builtins/i386/ashrdi3.S
+++ b/lib/builtins/i386/ashrdi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -22,10 +23,10 @@ DEFINE_COMPILERRT_FUNCTION(__ashrdi3)
#endif
psrlq %xmm2, %xmm0 // unsigned shift input by count
-
+
testl %eax, %eax // check the sign-bit of the input
jns 1f // early out for positive inputs
-
+
// If the input is negative, we need to construct the shifted sign bit
// to or into the result, as xmm does not have a signed right shift.
pcmpeqb %xmm1, %xmm1 // -1ULL
@@ -35,7 +36,7 @@ DEFINE_COMPILERRT_FUNCTION(__ashrdi3)
psubq %xmm1, %xmm2 // 64 - count
psllq %xmm2, %xmm1 // -1 << (64 - count) = leading sign bits
por %xmm1, %xmm0
-
+
// Move the result back to the general purpose registers and return
1: movd %xmm0, %eax
psrlq $32, %xmm0
@@ -51,14 +52,14 @@ DEFINE_COMPILERRT_FUNCTION(__ashrdi3)
movl 12(%esp), %ecx // Load count
movl 8(%esp), %edx // Load high
movl 4(%esp), %eax // Load low
-
+
testl $0x20, %ecx // If count >= 32
jnz 1f // goto 1
shrdl %cl, %edx, %eax // right shift low by count
sarl %cl, %edx // right shift high by count
ret
-
+
1: movl %edx, %eax // Move high to low
sarl $31, %edx // clear high
sarl %cl, %eax // shift low by count - 32
diff --git a/lib/builtins/i386/chkstk.S b/lib/builtins/i386/chkstk.S
index b59974868..f0bea2187 100644
--- a/lib/builtins/i386/chkstk.S
+++ b/lib/builtins/i386/chkstk.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/chkstk2.S b/lib/builtins/i386/chkstk2.S
index 7d65bb088..5d6cbdfa5 100644
--- a/lib/builtins/i386/chkstk2.S
+++ b/lib/builtins/i386/chkstk2.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/divdi3.S b/lib/builtins/i386/divdi3.S
index 2fb4bdcad..09e1e42eb 100644
--- a/lib/builtins/i386/divdi3.S
+++ b/lib/builtins/i386/divdi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -22,9 +23,9 @@
.balign 4
DEFINE_COMPILERRT_FUNCTION(__divdi3)
-/* This is currently implemented by wrapping the unsigned divide up in an absolute
- value, then restoring the correct sign at the end of the computation. This could
- certainly be improved upon. */
+// This is currently implemented by wrapping the unsigned divide up in an absolute
+// value, then restoring the correct sign at the end of the computation. This could
+// certainly be improved upon.
pushl %esi
movl 20(%esp), %edx // high word of b
@@ -38,7 +39,7 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
movl %edx, 20(%esp)
movl %eax, 16(%esp) // store abs(b) back to stack
movl %ecx, %esi // set aside sign of b
-
+
movl 12(%esp), %edx // high word of b
movl 8(%esp), %eax // low word of b
movl %edx, %ecx
@@ -55,11 +56,11 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
movl 24(%esp), %ebx // Find the index i of the leading bit in b.
bsrl %ebx, %ecx // If the high word of b is zero, jump to
jz 9f // the code to handle that special case [9].
-
- /* High word of b is known to be non-zero on this branch */
-
+
+ // High word of b is known to be non-zero on this branch
+
movl 20(%esp), %eax // Construct bhi, containing bits [1+i:32+i] of b
-
+
shrl %cl, %eax // Practically, this means that bhi is given by:
shrl %eax //
notl %ecx // bhi = (high word of b) << (31 - i) |
@@ -68,10 +69,10 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
movl 16(%esp), %edx // Load the high and low words of a, and jump
movl 12(%esp), %eax // to [1] if the high word is larger than bhi
cmpl %ebx, %edx // to avoid overflowing the upcoming divide.
- jae 1f
-
- /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+ jae 1f
+
+ // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
divl %ebx // eax <-- qs, edx <-- r such that ahi:alo = bs*qs + r
pushl %edi
@@ -90,7 +91,7 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
sbbl $0, %edi // decrement q if remainder is negative
xorl %edx, %edx
movl %edi, %eax
-
+
addl %esi, %eax // Restore correct sign to result
adcl %esi, %edx
xorl %esi, %eax
@@ -101,8 +102,8 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
retl // Return
-1: /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+1: // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
subl %ebx, %edx // subtract bhi from ahi so that divide will not
divl %ebx // overflow, and find q and r such that
//
@@ -128,7 +129,7 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
sbbl $0, %edi // decrement q if remainder is negative
xorl %edx, %edx
movl %edi, %eax
-
+
addl %esi, %eax // Restore correct sign to result
adcl %esi, %edx
xorl %esi, %eax
@@ -138,8 +139,8 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
popl %esi
retl // Return
-
-9: /* High word of b is zero on this branch */
+
+9: // High word of b is zero on this branch
movl 16(%esp), %eax // Find qhi and rhi such that
movl 20(%esp), %ecx //
@@ -149,7 +150,7 @@ DEFINE_COMPILERRT_FUNCTION(__divdi3)
movl 12(%esp), %eax // Find qlo such that
divl %ecx //
movl %ebx, %edx // rhi:alo = qlo*b + rlo with 0 ≤ rlo < b
-
+
addl %esi, %eax // Restore correct sign to result
adcl %esi, %edx
xorl %esi, %eax
diff --git a/lib/builtins/i386/floatdidf.S b/lib/builtins/i386/floatdidf.S
index d75dfe62d..ab7422c31 100644
--- a/lib/builtins/i386/floatdidf.S
+++ b/lib/builtins/i386/floatdidf.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/floatdisf.S b/lib/builtins/i386/floatdisf.S
index 0874eaaa9..d91f14e9f 100644
--- a/lib/builtins/i386/floatdisf.S
+++ b/lib/builtins/i386/floatdisf.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/floatdixf.S b/lib/builtins/i386/floatdixf.S
index 1044ef55a..df70f5f9e 100644
--- a/lib/builtins/i386/floatdixf.S
+++ b/lib/builtins/i386/floatdixf.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/floatundidf.S b/lib/builtins/i386/floatundidf.S
index fe032348e..8b1b666ce 100644
--- a/lib/builtins/i386/floatundidf.S
+++ b/lib/builtins/i386/floatundidf.S
@@ -1,9 +1,8 @@
//===-- floatundidf.S - Implement __floatundidf for i386 ------------------===//
//
-// The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
diff --git a/lib/builtins/i386/floatundisf.S b/lib/builtins/i386/floatundisf.S
index 16000b576..44301719e 100644
--- a/lib/builtins/i386/floatundisf.S
+++ b/lib/builtins/i386/floatundisf.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -48,7 +49,7 @@ END_COMPILERRT_FUNCTION(__floatundisf)
*/
-/* branch-free, x87-free implementation - faster at the expense of code size */
+// branch-free, x87-free implementation - faster at the expense of code size
#ifdef __i386__
@@ -78,7 +79,7 @@ DEFINE_COMPILERRT_FUNCTION(__floatundisf)
movd 8(%esp), %xmm1
movd 4(%esp), %xmm0
punpckldq %xmm1, %xmm0
-
+
calll 0f
0: popl %ecx
shrl %eax // high 31 bits of input as sint32
diff --git a/lib/builtins/i386/floatundixf.S b/lib/builtins/i386/floatundixf.S
index c935670cb..30b4d9f4b 100644
--- a/lib/builtins/i386/floatundixf.S
+++ b/lib/builtins/i386/floatundixf.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
diff --git a/lib/builtins/i386/lshrdi3.S b/lib/builtins/i386/lshrdi3.S
index 53e95cf76..896633e85 100644
--- a/lib/builtins/i386/lshrdi3.S
+++ b/lib/builtins/i386/lshrdi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -41,14 +42,14 @@ DEFINE_COMPILERRT_FUNCTION(__lshrdi3)
movl 12(%esp), %ecx // Load count
movl 8(%esp), %edx // Load high
movl 4(%esp), %eax // Load low
-
+
testl $0x20, %ecx // If count >= 32
jnz 1f // goto 1
shrdl %cl, %edx, %eax // right shift low by count
shrl %cl, %edx // right shift high by count
ret
-
+
1: movl %edx, %eax // Move high to low
xorl %edx, %edx // clear high
shrl %cl, %eax // shift low by count - 32
diff --git a/lib/builtins/i386/moddi3.S b/lib/builtins/i386/moddi3.S
index a5bf9ce8e..4580f20ea 100644
--- a/lib/builtins/i386/moddi3.S
+++ b/lib/builtins/i386/moddi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -23,8 +24,8 @@
.balign 4
DEFINE_COMPILERRT_FUNCTION(__moddi3)
-/* This is currently implemented by wrapping the unsigned modulus up in an absolute
- value. This could certainly be improved upon. */
+// This is currently implemented by wrapping the unsigned modulus up in an absolute
+// value. This could certainly be improved upon.
pushl %esi
movl 20(%esp), %edx // high word of b
@@ -37,7 +38,7 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
sbbl %ecx, %edx // EDX:EAX = abs(b)
movl %edx, 20(%esp)
movl %eax, 16(%esp) // store abs(b) back to stack
-
+
movl 12(%esp), %edx // high word of b
movl 8(%esp), %eax // low word of b
movl %edx, %ecx
@@ -54,11 +55,11 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
movl 24(%esp), %ebx // Find the index i of the leading bit in b.
bsrl %ebx, %ecx // If the high word of b is zero, jump to
jz 9f // the code to handle that special case [9].
-
- /* High word of b is known to be non-zero on this branch */
-
+
+ // High word of b is known to be non-zero on this branch
+
movl 20(%esp), %eax // Construct bhi, containing bits [1+i:32+i] of b
-
+
shrl %cl, %eax // Practically, this means that bhi is given by:
shrl %eax //
notl %ecx // bhi = (high word of b) << (31 - i) |
@@ -67,10 +68,10 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
movl 16(%esp), %edx // Load the high and low words of a, and jump
movl 12(%esp), %eax // to [2] if the high word is larger than bhi
cmpl %ebx, %edx // to avoid overflowing the upcoming divide.
- jae 2f
-
- /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+ jae 2f
+
+ // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
divl %ebx // eax <-- qs, edx <-- r such that ahi:alo = bs*qs + r
pushl %edi
@@ -86,13 +87,13 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
movl 28(%esp), %eax
imull %edi, %eax // q*bhi
subl %eax, %ecx // ECX:EBX = a - q*b
-
+
jnc 1f // if positive, this is the result.
addl 24(%esp), %ebx // otherwise
adcl 28(%esp), %ecx // ECX:EBX = a - (q-1)*b = result
1: movl %ebx, %eax
movl %ecx, %edx
-
+
addl %esi, %eax // Restore correct sign to result
adcl %esi, %edx
xorl %esi, %eax
@@ -102,8 +103,8 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
popl %esi
retl // Return
-2: /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+2: // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
subl %ebx, %edx // subtract bhi from ahi so that divide will not
divl %ebx // overflow, and find q and r such that
//
@@ -132,7 +133,7 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
adcl 28(%esp), %ecx // ECX:EBX = a - (q-1)*b = result
3: movl %ebx, %eax
movl %ecx, %edx
-
+
addl %esi, %eax // Restore correct sign to result
adcl %esi, %edx
xorl %esi, %eax
@@ -141,8 +142,8 @@ DEFINE_COMPILERRT_FUNCTION(__moddi3)
popl %ebx
popl %esi
retl // Return
-
-9: /* High word of b is zero on this branch */
+
+9: // High word of b is zero on this branch
movl 16(%esp), %eax // Find qhi and rhi such that
movl 20(%esp), %ecx //
diff --git a/lib/builtins/i386/muldi3.S b/lib/builtins/i386/muldi3.S
index 123946064..a898e2414 100644
--- a/lib/builtins/i386/muldi3.S
+++ b/lib/builtins/i386/muldi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -14,15 +15,15 @@ DEFINE_COMPILERRT_FUNCTION(__muldi3)
movl 16(%esp), %eax // b.lo
movl 12(%esp), %ecx // a.hi
imull %eax, %ecx // b.lo * a.hi
-
+
movl 8(%esp), %edx // a.lo
movl 20(%esp), %ebx // b.hi
imull %edx, %ebx // a.lo * b.hi
-
+
mull %edx // EDX:EAX = a.lo * b.lo
addl %ecx, %ebx // EBX = (a.lo*b.hi + a.hi*b.lo)
addl %ebx, %edx
-
+
popl %ebx
retl
END_COMPILERRT_FUNCTION(__muldi3)
diff --git a/lib/builtins/i386/udivdi3.S b/lib/builtins/i386/udivdi3.S
index 727613639..ca390245e 100644
--- a/lib/builtins/i386/udivdi3.S
+++ b/lib/builtins/i386/udivdi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -26,11 +27,11 @@ DEFINE_COMPILERRT_FUNCTION(__udivdi3)
movl 20(%esp), %ebx // Find the index i of the leading bit in b.
bsrl %ebx, %ecx // If the high word of b is zero, jump to
jz 9f // the code to handle that special case [9].
-
- /* High word of b is known to be non-zero on this branch */
-
+
+ // High word of b is known to be non-zero on this branch
+
movl 16(%esp), %eax // Construct bhi, containing bits [1+i:32+i] of b
-
+
shrl %cl, %eax // Practically, this means that bhi is given by:
shrl %eax //
notl %ecx // bhi = (high word of b) << (31 - i) |
@@ -39,10 +40,10 @@ DEFINE_COMPILERRT_FUNCTION(__udivdi3)
movl 12(%esp), %edx // Load the high and low words of a, and jump
movl 8(%esp), %eax // to [1] if the high word is larger than bhi
cmpl %ebx, %edx // to avoid overflowing the upcoming divide.
- jae 1f
-
- /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+ jae 1f
+
+ // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
divl %ebx // eax <-- qs, edx <-- r such that ahi:alo = bs*qs + r
pushl %edi
@@ -66,8 +67,8 @@ DEFINE_COMPILERRT_FUNCTION(__udivdi3)
retl
-1: /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+1: // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
subl %ebx, %edx // subtract bhi from ahi so that divide will not
divl %ebx // overflow, and find q and r such that
//
@@ -97,8 +98,8 @@ DEFINE_COMPILERRT_FUNCTION(__udivdi3)
popl %ebx
retl
-
-9: /* High word of b is zero on this branch */
+
+9: // High word of b is zero on this branch
movl 12(%esp), %eax // Find qhi and rhi such that
movl 16(%esp), %ecx //
diff --git a/lib/builtins/i386/umoddi3.S b/lib/builtins/i386/umoddi3.S
index 763e82194..2717e7e5d 100644
--- a/lib/builtins/i386/umoddi3.S
+++ b/lib/builtins/i386/umoddi3.S
@@ -1,5 +1,6 @@
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "../assembly.h"
@@ -27,11 +28,11 @@ DEFINE_COMPILERRT_FUNCTION(__umoddi3)
movl 20(%esp), %ebx // Find the index i of the leading bit in b.
bsrl %ebx, %ecx // If the high word of b is zero, jump to
jz 9f // the code to handle that special case [9].
-
- /* High word of b is known to be non-zero on this branch */
-
+
+ // High word of b is known to be non-zero on this branch
+
movl 16(%esp), %eax // Construct bhi, containing bits [1+i:32+i] of b
-
+
shrl %cl, %eax // Practically, this means that bhi is given by:
shrl %eax //
notl %ecx // bhi = (high word of b) << (31 - i) |
@@ -40,10 +41,10 @@ DEFINE_COMPILERRT_FUNCTION(__umoddi3)
movl 12(%esp), %edx // Load the high and low words of a, and jump
movl 8(%esp), %eax // to [2] if the high word is larger than bhi
cmpl %ebx, %edx // to avoid overflowing the upcoming divide.
- jae 2f
-
- /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+ jae 2f
+
+ // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
divl %ebx // eax <-- qs, edx <-- r such that ahi:alo = bs*qs + r
pushl %edi
@@ -59,20 +60,20 @@ DEFINE_COMPILERRT_FUNCTION(__umoddi3)
movl 24(%esp), %eax
imull %edi, %eax // q*bhi
subl %eax, %ecx // ECX:EBX = a - q*b
-
+
jnc 1f // if positive, this is the result.
addl 20(%esp), %ebx // otherwise
adcl 24(%esp), %ecx // ECX:EBX = a - (q-1)*b = result
1: movl %ebx, %eax
movl %ecx, %edx
-
+
popl %edi
popl %ebx
retl
-2: /* High word of a is greater than or equal to (b >> (1 + i)) on this branch */
-
+2: // High word of a is greater than or equal to (b >> (1 + i)) on this branch
+
subl %ebx, %edx // subtract bhi from ahi so that divide will not
divl %ebx // overflow, and find q and r such that
//
@@ -101,14 +102,14 @@ DEFINE_COMPILERRT_FUNCTION(__umoddi3)
adcl 24(%esp), %ecx // ECX:EBX = a - (q-1)*b = result
3: movl %ebx, %eax
movl %ecx, %edx
-
+
popl %edi
popl %ebx
retl
-
-9: /* High word of b is zero on this branch */
+
+9: // High word of b is zero on this branch
movl 12(%esp), %eax // Find qhi and rhi such that
movl 16(%esp), %ecx //
@@ -120,7 +121,7 @@ DEFINE_COMPILERRT_FUNCTION(__umoddi3)
movl %edx, %eax // rhi:alo = qlo*b + rlo with 0 ≤ rlo < b
popl %ebx //
xorl %edx, %edx // and return 0:rlo
- retl //
+ retl //
END_COMPILERRT_FUNCTION(__umoddi3)
#endif // __i386__
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