* [PATCH v3] MdePkg/BaseLib: Add bit field population calculating methods
@ 2018-07-04 14:02 Tomas Pilar (tpilar)
2018-07-05 14:07 ` Gao, Liming
0 siblings, 1 reply; 3+ messages in thread
From: Tomas Pilar (tpilar) @ 2018-07-04 14:02 UTC (permalink / raw)
To: edk2-devel; +Cc: Michael D Kinney, Liming Gao
Add 32-bit and 64-bit functions that count number of set bits in a bitfield
using a divide-and-count method.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Tomas Pilar <tpilar@solarflare.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
---
MdePkg/Include/Library/BaseLib.h | 56 ++++++++++++++++++++++++++
MdePkg/Library/BaseLib/BitField.c | 85 +++++++++++++++++++++++++++++++++++++++
2 files changed, 141 insertions(+)
diff --git a/MdePkg/Include/Library/BaseLib.h b/MdePkg/Include/Library/BaseLib.h
index 1db3a04..123ae19 100644
--- a/MdePkg/Include/Library/BaseLib.h
+++ b/MdePkg/Include/Library/BaseLib.h
@@ -4609,6 +4609,62 @@ BitFieldAndThenOr64 (
IN UINT64 OrData
);
+/**
+ Reads a bit field from a 32-bit value, counts and returns
+ the number of set bits.
+
+ Counts the number of set bits in the bit field specified by
+ StartBit and EndBit in Operand. The count is returned.
+
+ If StartBit is greater than 31, then ASSERT().
+ If EndBit is greater than 31, then ASSERT().
+ If EndBit is less than StartBit, then ASSERT().
+
+ @param Operand Operand on which to perform the bitfield operation.
+ @param StartBit The ordinal of the least significant bit in the bit field.
+ Range 0..31.
+ @param EndBit The ordinal of the most significant bit in the bit field.
+ Range 0..31.
+
+ @return The number of bits set between StartBit and EndBit.
+
+**/
+UINT8
+EFIAPI
+BitFieldCountOnes32 (
+ IN UINT32 Operand,
+ IN UINTN StartBit,
+ IN UINTN EndBit
+ );
+
+/**
+ Reads a bit field from a 64-bit value, counts and returns
+ the number of set bits.
+
+ Counts the number of set bits in the bit field specified by
+ StartBit and EndBit in Operand. The count is returned.
+
+ If StartBit is greater than 63, then ASSERT().
+ If EndBit is greater than 63, then ASSERT().
+ If EndBit is less than StartBit, then ASSERT().
+
+ @param Operand Operand on which to perform the bitfield operation.
+ @param StartBit The ordinal of the least significant bit in the bit field.
+ Range 0..63.
+ @param EndBit The ordinal of the most significant bit in the bit field.
+ Range 0..63.
+
+ @return The number of bits set between StartBit and EndBit.
+
+**/
+UINT8
+EFIAPI
+BitFieldCountOnes64 (
+ IN UINT64 Operand,
+ IN UINTN StartBit,
+ IN UINTN EndBit
+ );
+
//
// Base Library Checksum Functions
//
diff --git a/MdePkg/Library/BaseLib/BitField.c b/MdePkg/Library/BaseLib/BitField.c
index d2d3150..8acd345 100644
--- a/MdePkg/Library/BaseLib/BitField.c
+++ b/MdePkg/Library/BaseLib/BitField.c
@@ -920,3 +920,88 @@ BitFieldAndThenOr64 (
OrData
);
}
+
+/**
+ Reads a bit field from a 32-bit value, counts and returns
+ the number of set bits.
+
+ Counts the number of set bits in the bit field specified by
+ StartBit and EndBit in Operand. The count is returned.
+
+ If StartBit is greater than 31, then ASSERT().
+ If EndBit is greater than 31, then ASSERT().
+ If EndBit is less than StartBit, then ASSERT().
+
+ @param Operand Operand on which to perform the bitfield operation.
+ @param StartBit The ordinal of the least significant bit in the bit field.
+ Range 0..31.
+ @param EndBit The ordinal of the most significant bit in the bit field.
+ Range 0..31.
+
+ @return The number of bits set between StartBit and EndBit.
+
+**/
+UINT8
+EFIAPI
+BitFieldCountOnes32 (
+ IN UINT32 Operand,
+ IN UINTN StartBit,
+ IN UINTN EndBit
+ )
+{
+ UINT32 Count;
+
+ ASSERT (EndBit < 32);
+ ASSERT (StartBit <= EndBit);
+
+ Count = BitFieldRead32 (Operand, StartBit, EndBit);
+ Count -= ((Count >> 1) & 0x55555555);
+ Count = (Count & 0x33333333) + ((Count >> 2) & 0x33333333);
+ Count += Count >> 4;
+ Count &= 0x0F0F0F0F;
+ Count += Count >> 8;
+ Count += Count >> 16;
+
+ return (UINT8) Count & 0x3F;
+}
+
+/**
+ Reads a bit field from a 64-bit value, counts and returns
+ the number of set bits.
+
+ Counts the number of set bits in the bit field specified by
+ StartBit and EndBit in Operand. The count is returned.
+
+ If StartBit is greater than 63, then ASSERT().
+ If EndBit is greater than 63, then ASSERT().
+ If EndBit is less than StartBit, then ASSERT().
+
+ @param Operand Operand on which to perform the bitfield operation.
+ @param StartBit The ordinal of the least significant bit in the bit field.
+ Range 0..63.
+ @param EndBit The ordinal of the most significant bit in the bit field.
+ Range 0..63.
+
+ @return The number of bits set between StartBit and EndBit.
+
+**/
+UINT8
+EFIAPI
+BitFieldCountOnes64 (
+ IN UINT64 Operand,
+ IN UINTN StartBit,
+ IN UINTN EndBit
+ )
+{
+ UINT32 BitField;
+ UINT8 Count;
+
+ ASSERT (EndBit < 64);
+ ASSERT (StartBit <= EndBit);
+
+ BitField = BitFieldRead64 (Operand, StartBit, EndBit);
+ Count = BitFieldCountOnes32 (BitField, 0, 31);
+
+ return Count + BitFieldCountOnes32 (RShiftU64(BitField, 32), 0, 31);
+}
+
--
2.9.5
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v3] MdePkg/BaseLib: Add bit field population calculating methods
2018-07-04 14:02 [PATCH v3] MdePkg/BaseLib: Add bit field population calculating methods Tomas Pilar (tpilar)
@ 2018-07-05 14:07 ` Gao, Liming
2018-07-06 13:39 ` Tomas Pilar (tpilar)
0 siblings, 1 reply; 3+ messages in thread
From: Gao, Liming @ 2018-07-05 14:07 UTC (permalink / raw)
To: Tomas Pilar (tpilar), edk2-devel@lists.01.org; +Cc: Kinney, Michael D
Tom:
When I use VS2015 to compile it, I meet with below error. Could you fix them?
Edk2\MdePkg\Library\BaseLib\BitField.c(1002): error C2220: warning treated as error - no 'object' file generated
Edk2\MdePkg\Library\BaseLib\BitField.c(1002): warning C4244: '=': conversion from 'UINT64' to 'UINT32', possible loss of data
Edk2\MdePkg\Library\BaseLib\BitField.c(1005): warning C4244: 'function': conversion from 'UINT64' to 'UINT32', possible loss of data
Thanks
Liming
> -----Original Message-----
> From: Tomas Pilar (tpilar) [mailto:tpilar@solarflare.com]
> Sent: Wednesday, July 4, 2018 10:02 PM
> To: edk2-devel@lists.01.org
> Cc: Kinney, Michael D <michael.d.kinney@intel.com>; Gao, Liming <liming.gao@intel.com>
> Subject: [PATCH v3] MdePkg/BaseLib: Add bit field population calculating methods
>
> Add 32-bit and 64-bit functions that count number of set bits in a bitfield
> using a divide-and-count method.
>
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Tomas Pilar <tpilar@solarflare.com>
> Cc: Liming Gao <liming.gao@intel.com>
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> ---
> MdePkg/Include/Library/BaseLib.h | 56 ++++++++++++++++++++++++++
> MdePkg/Library/BaseLib/BitField.c | 85 +++++++++++++++++++++++++++++++++++++++
> 2 files changed, 141 insertions(+)
>
> diff --git a/MdePkg/Include/Library/BaseLib.h b/MdePkg/Include/Library/BaseLib.h
> index 1db3a04..123ae19 100644
> --- a/MdePkg/Include/Library/BaseLib.h
> +++ b/MdePkg/Include/Library/BaseLib.h
> @@ -4609,6 +4609,62 @@ BitFieldAndThenOr64 (
> IN UINT64 OrData
> );
>
> +/**
> + Reads a bit field from a 32-bit value, counts and returns
> + the number of set bits.
> +
> + Counts the number of set bits in the bit field specified by
> + StartBit and EndBit in Operand. The count is returned.
> +
> + If StartBit is greater than 31, then ASSERT().
> + If EndBit is greater than 31, then ASSERT().
> + If EndBit is less than StartBit, then ASSERT().
> +
> + @param Operand Operand on which to perform the bitfield operation.
> + @param StartBit The ordinal of the least significant bit in the bit field.
> + Range 0..31.
> + @param EndBit The ordinal of the most significant bit in the bit field.
> + Range 0..31.
> +
> + @return The number of bits set between StartBit and EndBit.
> +
> +**/
> +UINT8
> +EFIAPI
> +BitFieldCountOnes32 (
> + IN UINT32 Operand,
> + IN UINTN StartBit,
> + IN UINTN EndBit
> + );
> +
> +/**
> + Reads a bit field from a 64-bit value, counts and returns
> + the number of set bits.
> +
> + Counts the number of set bits in the bit field specified by
> + StartBit and EndBit in Operand. The count is returned.
> +
> + If StartBit is greater than 63, then ASSERT().
> + If EndBit is greater than 63, then ASSERT().
> + If EndBit is less than StartBit, then ASSERT().
> +
> + @param Operand Operand on which to perform the bitfield operation.
> + @param StartBit The ordinal of the least significant bit in the bit field.
> + Range 0..63.
> + @param EndBit The ordinal of the most significant bit in the bit field.
> + Range 0..63.
> +
> + @return The number of bits set between StartBit and EndBit.
> +
> +**/
> +UINT8
> +EFIAPI
> +BitFieldCountOnes64 (
> + IN UINT64 Operand,
> + IN UINTN StartBit,
> + IN UINTN EndBit
> + );
> +
> //
> // Base Library Checksum Functions
> //
> diff --git a/MdePkg/Library/BaseLib/BitField.c b/MdePkg/Library/BaseLib/BitField.c
> index d2d3150..8acd345 100644
> --- a/MdePkg/Library/BaseLib/BitField.c
> +++ b/MdePkg/Library/BaseLib/BitField.c
> @@ -920,3 +920,88 @@ BitFieldAndThenOr64 (
> OrData
> );
> }
> +
> +/**
> + Reads a bit field from a 32-bit value, counts and returns
> + the number of set bits.
> +
> + Counts the number of set bits in the bit field specified by
> + StartBit and EndBit in Operand. The count is returned.
> +
> + If StartBit is greater than 31, then ASSERT().
> + If EndBit is greater than 31, then ASSERT().
> + If EndBit is less than StartBit, then ASSERT().
> +
> + @param Operand Operand on which to perform the bitfield operation.
> + @param StartBit The ordinal of the least significant bit in the bit field.
> + Range 0..31.
> + @param EndBit The ordinal of the most significant bit in the bit field.
> + Range 0..31.
> +
> + @return The number of bits set between StartBit and EndBit.
> +
> +**/
> +UINT8
> +EFIAPI
> +BitFieldCountOnes32 (
> + IN UINT32 Operand,
> + IN UINTN StartBit,
> + IN UINTN EndBit
> + )
> +{
> + UINT32 Count;
> +
> + ASSERT (EndBit < 32);
> + ASSERT (StartBit <= EndBit);
> +
> + Count = BitFieldRead32 (Operand, StartBit, EndBit);
> + Count -= ((Count >> 1) & 0x55555555);
> + Count = (Count & 0x33333333) + ((Count >> 2) & 0x33333333);
> + Count += Count >> 4;
> + Count &= 0x0F0F0F0F;
> + Count += Count >> 8;
> + Count += Count >> 16;
> +
> + return (UINT8) Count & 0x3F;
> +}
> +
> +/**
> + Reads a bit field from a 64-bit value, counts and returns
> + the number of set bits.
> +
> + Counts the number of set bits in the bit field specified by
> + StartBit and EndBit in Operand. The count is returned.
> +
> + If StartBit is greater than 63, then ASSERT().
> + If EndBit is greater than 63, then ASSERT().
> + If EndBit is less than StartBit, then ASSERT().
> +
> + @param Operand Operand on which to perform the bitfield operation.
> + @param StartBit The ordinal of the least significant bit in the bit field.
> + Range 0..63.
> + @param EndBit The ordinal of the most significant bit in the bit field.
> + Range 0..63.
> +
> + @return The number of bits set between StartBit and EndBit.
> +
> +**/
> +UINT8
> +EFIAPI
> +BitFieldCountOnes64 (
> + IN UINT64 Operand,
> + IN UINTN StartBit,
> + IN UINTN EndBit
> + )
> +{
> + UINT32 BitField;
> + UINT8 Count;
> +
> + ASSERT (EndBit < 64);
> + ASSERT (StartBit <= EndBit);
> +
> + BitField = BitFieldRead64 (Operand, StartBit, EndBit);
> + Count = BitFieldCountOnes32 (BitField, 0, 31);
> +
> + return Count + BitFieldCountOnes32 (RShiftU64(BitField, 32), 0, 31);
> +}
> +
> --
> 2.9.5
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v3] MdePkg/BaseLib: Add bit field population calculating methods
2018-07-05 14:07 ` Gao, Liming
@ 2018-07-06 13:39 ` Tomas Pilar (tpilar)
0 siblings, 0 replies; 3+ messages in thread
From: Tomas Pilar (tpilar) @ 2018-07-06 13:39 UTC (permalink / raw)
To: Gao, Liming, edk2-devel@lists.01.org; +Cc: Kinney, Michael D
Apologies, I usually compile with GCC49 since I work on linux. Respinning now.
Cheers
Tom
On 05/07/18 15:07, Gao, Liming wrote:
> warning C4244
^ permalink raw reply [flat|nested] 3+ messages in thread
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2018-07-06 13:39 ` Tomas Pilar (tpilar)
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