For whatever the reason, x86 CallingConv::Fast (i.e. fastcc) was not passing scalar arguments in registers. This patch defines a new fastcc CC which is slightly different from the FastCall CC. In addition to passing integer arguments in ECX and EDX, it also specify doubles are passed in 8-byte slots which are 8-byte aligned (instead of 4-byte aligned). This avoids a potential performance hazard where doubles span cacheline boundaries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55807 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2008-09-04 22:59:58 +00:00
parent deafefabae
commit 4a03775777
7 changed files with 53 additions and 16 deletions

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@ -341,3 +341,20 @@ def CC_X86_32_FastCall : CallingConv<[
// Otherwise, same as everything else.
CCDelegateTo<CC_X86_32_Common>
]>;
def CC_X86_32_FastCC : CallingConv<[
// Promote i8/i16 arguments to i32.
CCIfType<[i8, i16], CCPromoteToType<i32>>,
// The 'nest' parameter, if any, is passed in EAX.
CCIfNest<CCAssignToReg<[EAX]>>,
// The first 2 integer arguments are passed in ECX/EDX
CCIfType<[i32], CCAssignToReg<[ECX, EDX]>>,
// Doubles get 8-byte slots that are 8-byte aligned.
CCIfType<[f64], CCAssignToStack<8, 8>>,
// Otherwise, same as everything else.
CCDelegateTo<CC_X86_32_Common>
]>;

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@ -1100,6 +1100,8 @@ CCAssignFn *X86TargetLowering::CCAssignFnForNode(SDValue Op) const {
return CC_X86_32_FastCall;
else if (CC == CallingConv::Fast && PerformTailCallOpt)
return CC_X86_32_TailCall;
else if (CC == CallingConv::Fast)
return CC_X86_32_FastCC;
else
return CC_X86_32_C;
}

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@ -6,9 +6,9 @@
@rtx_format = external global [116 x i8*] ; <[116 x i8*]*> [#uses=1]
@rtx_length = external global [117 x i32] ; <[117 x i32]*> [#uses=1]
declare fastcc %struct.rtx_def* @fixup_memory_subreg(%struct.rtx_def*, %struct.rtx_def*, i32)
declare %struct.rtx_def* @fixup_memory_subreg(%struct.rtx_def*, %struct.rtx_def*, i32)
define fastcc %struct.rtx_def* @walk_fixup_memory_subreg(%struct.rtx_def* %x, %struct.rtx_def* %insn) {
define %struct.rtx_def* @walk_fixup_memory_subreg(%struct.rtx_def* %x, %struct.rtx_def* %insn) {
entry:
%tmp2 = icmp eq %struct.rtx_def* %x, null ; <i1> [#uses=1]
br i1 %tmp2, label %UnifiedReturnBlock, label %cond_next
@ -30,7 +30,7 @@ cond_true13: ; preds = %cond_next
br i1 %tmp22, label %cond_true25, label %cond_next32
cond_true25: ; preds = %cond_true13
%tmp29 = tail call fastcc %struct.rtx_def* @fixup_memory_subreg( %struct.rtx_def* %x, %struct.rtx_def* %insn, i32 1 ) ; <%struct.rtx_def*> [#uses=1]
%tmp29 = tail call %struct.rtx_def* @fixup_memory_subreg( %struct.rtx_def* %x, %struct.rtx_def* %insn, i32 1 ) ; <%struct.rtx_def*> [#uses=1]
ret %struct.rtx_def* %tmp29
cond_next32: ; preds = %cond_true13, %cond_next
@ -56,7 +56,7 @@ cond_true47: ; preds = %bb
%tmp52 = getelementptr %struct.rtx_def* %x, i32 0, i32 3, i32 %i.01.0 ; <%struct..0anon*> [#uses=1]
%tmp5354 = bitcast %struct..0anon* %tmp52 to %struct.rtx_def** ; <%struct.rtx_def**> [#uses=1]
%tmp55 = load %struct.rtx_def** %tmp5354 ; <%struct.rtx_def*> [#uses=1]
%tmp58 = tail call fastcc %struct.rtx_def* @walk_fixup_memory_subreg( %struct.rtx_def* %tmp55, %struct.rtx_def* %insn ) ; <%struct.rtx_def*> [#uses=1]
%tmp58 = tail call %struct.rtx_def* @walk_fixup_memory_subreg( %struct.rtx_def* %tmp55, %struct.rtx_def* %insn ) ; <%struct.rtx_def*> [#uses=1]
%tmp62 = getelementptr %struct.rtx_def* %x, i32 0, i32 3, i32 %i.01.0, i32 0 ; <i32*> [#uses=1]
%tmp58.c = ptrtoint %struct.rtx_def* %tmp58 to i32 ; <i32> [#uses=1]
store i32 %tmp58.c, i32* %tmp62
@ -79,7 +79,7 @@ bb73: ; preds = %bb73, %bb105.preheader
%tmp92 = getelementptr %struct.rtvec_def* %tmp81, i32 0, i32 1, i32 %j.019 ; <%struct..0anon*> [#uses=1]
%tmp9394 = bitcast %struct..0anon* %tmp92 to %struct.rtx_def** ; <%struct.rtx_def**> [#uses=1]
%tmp95 = load %struct.rtx_def** %tmp9394 ; <%struct.rtx_def*> [#uses=1]
%tmp98 = tail call fastcc %struct.rtx_def* @walk_fixup_memory_subreg( %struct.rtx_def* %tmp95, %struct.rtx_def* %insn ) ; <%struct.rtx_def*> [#uses=1]
%tmp98 = tail call %struct.rtx_def* @walk_fixup_memory_subreg( %struct.rtx_def* %tmp95, %struct.rtx_def* %insn ) ; <%struct.rtx_def*> [#uses=1]
%tmp101 = getelementptr %struct.rtvec_def* %tmp81, i32 0, i32 1, i32 %j.019, i32 0 ; <i32*> [#uses=1]
%tmp98.c = ptrtoint %struct.rtx_def* %tmp98 to i32 ; <i32> [#uses=1]
store i32 %tmp98.c, i32* %tmp101

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@ -4,7 +4,7 @@
%struct.quad_struct = type { i32, i32, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct* }
define fastcc %struct.quad_struct* @MakeTree(i32 %size, i32 %center_x, i32 %center_y, i32 %lo_proc, i32 %hi_proc, %struct.quad_struct* %parent, i32 %ct, i32 %level) nounwind {
define %struct.quad_struct* @MakeTree(i32 %size, i32 %center_x, i32 %center_y, i32 %lo_proc, i32 %hi_proc, %struct.quad_struct* %parent, i32 %ct, i32 %level) nounwind {
entry:
br i1 true, label %bb43.i, label %bb.i
@ -39,12 +39,12 @@ bb34: ; preds = %CheckOutside.exit20.i
%tmp15.reg2mem.0 = sdiv i32 %size, 2 ; <i32> [#uses=7]
%tmp85 = sub i32 %center_y, %tmp15.reg2mem.0 ; <i32> [#uses=2]
%tmp88 = sub i32 %center_x, %tmp15.reg2mem.0 ; <i32> [#uses=2]
%tmp92 = tail call fastcc %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 %tmp88, i32 %tmp85, i32 0, i32 %hi_proc, %struct.quad_struct* null, i32 2, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp92 = tail call %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 %tmp88, i32 %tmp85, i32 0, i32 %hi_proc, %struct.quad_struct* null, i32 2, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp99 = add i32 0, %hi_proc ; <i32> [#uses=1]
%tmp100 = sdiv i32 %tmp99, 2 ; <i32> [#uses=1]
%tmp110 = tail call fastcc %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 0, i32 %tmp85, i32 0, i32 %tmp100, %struct.quad_struct* null, i32 3, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp110 = tail call %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 0, i32 %tmp85, i32 0, i32 %tmp100, %struct.quad_struct* null, i32 3, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp122 = add i32 %tmp15.reg2mem.0, %center_y ; <i32> [#uses=2]
%tmp129 = tail call fastcc %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 0, i32 %tmp122, i32 0, i32 0, %struct.quad_struct* null, i32 1, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp147 = tail call fastcc %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 %tmp88, i32 %tmp122, i32 %lo_proc, i32 0, %struct.quad_struct* null, i32 0, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp129 = tail call %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 0, i32 %tmp122, i32 0, i32 0, %struct.quad_struct* null, i32 1, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
%tmp147 = tail call %struct.quad_struct* @MakeTree( i32 %tmp15.reg2mem.0, i32 %tmp88, i32 %tmp122, i32 %lo_proc, i32 0, %struct.quad_struct* null, i32 0, i32 0 ) nounwind ; <%struct.quad_struct*> [#uses=0]
unreachable
}

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@ -2,7 +2,7 @@
%struct.quad_struct = type { i32, i32, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct* }
define fastcc i32 @perimeter(%struct.quad_struct* %tree, i32 %size) nounwind {
define i32 @perimeter(%struct.quad_struct* %tree, i32 %size) nounwind {
entry:
switch i32 %size, label %UnifiedReturnBlock [
i32 2, label %bb
@ -10,8 +10,8 @@ entry:
]
bb: ; preds = %entry
%tmp31 = tail call fastcc i32 @perimeter( %struct.quad_struct* null, i32 0 ) nounwind ; <i32> [#uses=1]
%tmp40 = tail call fastcc i32 @perimeter( %struct.quad_struct* null, i32 0 ) nounwind ; <i32> [#uses=1]
%tmp31 = tail call i32 @perimeter( %struct.quad_struct* null, i32 0 ) nounwind ; <i32> [#uses=1]
%tmp40 = tail call i32 @perimeter( %struct.quad_struct* null, i32 0 ) nounwind ; <i32> [#uses=1]
%tmp33 = add i32 0, %tmp31 ; <i32> [#uses=1]
%tmp42 = add i32 %tmp33, %tmp40 ; <i32> [#uses=1]
ret i32 %tmp42

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@ -1,7 +1,6 @@
; RUN: llvm-as < %s | llc -march=x86 -mattr=+sse2 | grep movsd
; RUN: llvm-as < %s | llc -march=x86 -mattr=+sse2 | grep mov | count 1
; RUN: llvm-as < %s | llc -march=x86 -mattr=+sse2 | grep fldl | count 1
define fastcc double @doload64(i64 %x) nounwind {
define double @doload64(i64 %x) nounwind {
%tmp717 = bitcast i64 %x to double
ret double %tmp717
}

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@ -0,0 +1,19 @@
; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin | grep mov | grep ecx | grep 0
; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin | grep mov | grep xmm0 | grep 16
@d = external global double ; <double*> [#uses=1]
@c = external global double ; <double*> [#uses=1]
@b = external global double ; <double*> [#uses=1]
@a = external global double ; <double*> [#uses=1]
define i32 @foo() nounwind {
entry:
%0 = load double* @d, align 8 ; <double> [#uses=1]
%1 = load double* @c, align 8 ; <double> [#uses=1]
%2 = load double* @b, align 8 ; <double> [#uses=1]
%3 = load double* @a, align 8 ; <double> [#uses=1]
tail call fastcc void @bar( i32 0, i32 1, i32 2, double 1.000000e+00, double %3, double %2, double %1, double %0 ) nounwind
ret i32 0
}
declare fastcc void @bar(i32, i32, i32, double, double, double, double, double)