diff options
| author | Cherry Zhang <cherryyz@google.com> | 2017-04-06 10:01:36 -0400 |
|---|---|---|
| committer | Cherry Zhang <cherryyz@google.com> | 2017-04-06 17:59:39 +0000 |
| commit | 0bae9b083bdbf4d15d65fe175eaa98e4a83d22ea (patch) | |
| tree | 5cc3b30c54441aa6b03748bc693313f112bede38 /src/cmd/internal/obj/arm64/a.out.go | |
| parent | 257b01f8f47ace2ddd75efe37d8a0353888bce14 (diff) | |
| download | go-0bae9b083bdbf4d15d65fe175eaa98e4a83d22ea.tar.xz | |
cmd/internal/obj/arm64: fix encoding of AND MBCON
When a constant is both MOVCON (can fit into a MOV instruction)
and BITCON (can fit into a logical instruction), the assembler
chooses to use the MOVCON encoding, which is actually longer for
logical instructions. We add MBCON rules explicitly to make sure
it uses the BITCON encoding.
Updates #19857.
Change-Id: Ib9881be363cbc491ac2a0792b36b87e74eff34a8
Reviewed-on: https://go-review.googlesource.com/39652
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Diffstat (limited to 'src/cmd/internal/obj/arm64/a.out.go')
| -rw-r--r-- | src/cmd/internal/obj/arm64/a.out.go | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/src/cmd/internal/obj/arm64/a.out.go b/src/cmd/internal/obj/arm64/a.out.go index bed129d891..f192a51b0a 100644 --- a/src/cmd/internal/obj/arm64/a.out.go +++ b/src/cmd/internal/obj/arm64/a.out.go @@ -254,6 +254,9 @@ const ( ) const ( + // optab is sorted based on the order of these constants + // and the first match is chosen. + // The more specific class needs to come earlier. C_NONE = iota C_REG // R0..R30 C_RSP // R0..R30, RSP @@ -266,13 +269,13 @@ const ( C_COND // EQ, NE, etc C_ZCON // $0 or ZR + C_ABCON0 // could be C_ADDCON0 or C_BITCON C_ADDCON0 // 12-bit unsigned, unshifted + C_ABCON // could be C_ADDCON or C_BITCON C_ADDCON // 12-bit unsigned, shifted left by 0 or 12 + C_MBCON // could be C_MOVCON or C_BITCON C_MOVCON // generated by a 16-bit constant, optionally inverted and/or shifted by multiple of 16 C_BITCON // bitfield and logical immediate masks - C_ABCON0 // could be C_ADDCON0 or C_BITCON - C_ABCON // could be C_ADDCON or C_BITCON - C_MBCON // could be C_MOVCON or C_BITCON C_LCON // 32-bit constant C_VCON // 64-bit constant C_FCON // floating-point constant |